Encoding method and communications device

ABSTRACT

Embodiments disclose an encoding method and a communications device. The method includes: obtaining and encoding a to-be-encoded information bit sequence based on a binary vector P 1  of a first code, to obtain and output an encoded bit sequence, where P 1  is determined based on a binary vector P 2  of a second code and a binary vector P 3  of a third code, P 1 , P 2 , and P 3  indicate an information bit and a frozen bit of the first code, the second code and the third code respectively, a code length of the first code, the second code and the third code is n 3 , n 2  and n 3  respectively, a quantity of information bits of the first code, the second code and the third code is k 1 , k 2  and k 3  respectively, n 1 =n 2 *n 3 , and k 1 =k 2 *k 3 . Therefore, parallel decoding can be performed, helping reduce a decoding delay.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No. PCT/CN2020/082846, filed on Apr. 1, 2020, which claims priority to Chinese Patent Application No. 202010075805.8, filed on Jan. 22, 2020 and Chinese Patent Application No. 201910357715.5, filed on Apr. 29, 2019. All of the aforementioned patent applications are hereby incorporated by reference in their entireties.

TECHNICAL FIELD

The embodiments relate to the field of communications technologies, and in particular to an encoding method and a communications device.

BACKGROUND

Rapid evolution of wireless communication indicates that a 5G communications system will present some new features in the future. Three most typical communication scenarios include an enhanced mobile broadband (eMBB) scenario, a massive machine-type communication (mMTC) scenario, and an ultra-reliable low-latency communication (URLLC) scenario. Demands of these communication scenarios pose new challenges to an existing LTE technology.

In a communications system, channel encoding is usually used to improve data transmission reliability. As a most basic radio access technology, channel encoding is one of important research objects that meet 5G communication requirements. Since the Shannon theory was put forward, scholars in various countries have being devoted to finding an encoding and decoding method that can reach a Shannon limit and that has relatively low complexity. A polar code is an encoding scheme that is proposed based on channel polarization. A polar code is the first and the only channel encoding method that is currently known and can strictly provably “reach” a channel capacity.

During actual application, it is found that, when decoding is performed on a bit sequence encoded by using a polar code, serial decoding needs to be performed on all information bits. This causes a relatively long decoding delay. Therefore, currently, a new encoding method needs to be urgently provided, so that parallel decoding can be performed on all the information bits during decoding, to reduce the decoding delay.

SUMMARY

Embodiments provide an encoding method and a communications device, to help reduce a decoding delay.

According to a first aspect, an embodiment provides an encoding method. The method includes: obtaining a to-be-encoded information bit sequence; encoding the to-be-encoded information bit sequence based on a binary vector P₁ of a first code, to obtain an encoded bit sequence, where P₁ is determined based on a binary vector P₂ of a second code and a binary vector P₃ of a third code, P₁ indicates an information bit and a frozen bit of the first code, P₂ indicates an information bit and a frozen bit of the second code, P₃ indicates an information bit and a frozen bit of the third code, a code length of the first code is n₃, a quantity of information bits of the first code is k₁, a code length of the second code is n₂, a quantity of information bits of the second code is k₂, a code length of the third code is n₃, a quantity of information bits of the third code is k₃, n₁=n₂*n₃, and k₁=k₂*k₃; and outputting the encoded bit sequence. When encoding is performed in the encoding manner described in the first aspect, parallel decoding can be performed in a decoding process. This helps reduce a decoding delay.

In an optional implementation, P₁=P₂⊗P₃. Based on this optional implementation, a Kronecker product operation can be performed on P₂ and P₃, to obtain P₁.

In an optional implementation, n₂=n₃ and k₂=k₃. Based on this optional implementation, the first code can be constructed based on two codes that have a same code length and a same quantity of information bits. This facilitates implementation.

In an optional implementation, n₂=n₃, k₂=k₃, and P₂ is equal to P₃. Based on this optional implementation, the second code and the third code may actually be understood as a same code. Therefore, the first code can be constructed based on one code. This facilitates implementation.

In an optional implementation, k₁=k₄, and k₄ is a length of the to-be-encoded information bit sequence. Based on this optional implementation, the first code whose quantity of information bits is equal to the length of the to-be-encoded information bit sequence can be constructed. After the first code is constructed, the information bit of the first code can be directly filled with information in the to-be-encoded information bit sequence, the frozen bit of the first code can be directly filled with a fixed value, and then a bit vector obtained after filling of bit values is encoded.

In an optional implementation, k₄<k₁, k₁=┌√{square root over (k₄)}┐², and k4 is a length of the to-be-encoded information bit sequence. Based on this optional implementation, the first code whose quantity of information bits is greater than the length of the to-be-encoded information bit sequence can be constructed, and then the to-be-encoded information bit sequence is encoded based on P₁ of the first code.

In an optional implementation, the encoding the to-be-encoded information bit sequence based on a binary vector P₁ of a first code is implemented in the following manner: determining, based on P₁, a binary vector P₄ corresponding to a fourth code, where P₄ indicates an information bit and a frozen bit of the fourth code, a code length of the fourth code is n₄, a quantity of information bits of the fourth code is k⁴, and n₄=n₁; and encoding the to-be-encoded information bit sequence based on P₄. Based on this optional implementation, the fourth code can be constructed based on the first code, and then the to-be-encoded information bit sequence is encoded based on P₄ of the fourth code.

In an optional implementation, a set S₂ is a subset of a set S₁, the set S₁ is an information bit set including the information bit indicated by P₁, and S₂ is an information bit set including the information bit indicated by P₄. Based on this optional implementation, a part of the information bit indicated by P₁ is changed to a frozen bit. In this way, P₄ can be obtained.

In an optional implementation, the determining, based on P₁, a binary vector P₄ corresponding to a fourth code is implemented in the following manner: determining a set S₃ from the set S₁, where when an information bit included in the set S₃ is changed to a frozen bit, at least one information bit of a first inner code can be changed to a frozen bit in a first encoding process; determining a first information bit from the set S₃; changing the first information bit in P₁ to a frozen bit, to obtain a binary vector P₅; and obtaining the binary vector P₄ corresponding to the fourth code based on the binary vector P₅. Based on this optional implementation, the fourth code is constructed. This helps reduce a code rate of an inner code.

In an optional implementation, the set S₃ includes a plurality of information bits; and compared with another information bit in the set S₃, when the first information bit in the set S₃ is changed to a frozen bit, an information bit that is of the first inner code and that is changed to a frozen bit has a lowest reliability rank. Based on this optional implementation, the fourth code is constructed. This helps reduce a code rate of an inner code and improve transmission reliability.

In an optional implementation, the obtaining the binary vector P₄ corresponding to the fourth code based on the binary vector P₅ is implemented in the following manner: determining a set S₄ from an information bit indicated by P₅, where when an information bit included in the set S₄ is changed to a frozen bit, at least one information bit of a second inner code can be changed to a frozen bit in a second encoding process, the first inner code is an outer code for the second encoding process, and the second inner code is an outer code for the first encoding process; determining a second information bit from the set S₄; changing the second information bit in P₅ to a frozen bit, to obtain a binary vector P₆; and obtaining the binary vector corresponding to the fourth code based on the binary vector P₆. Based on this optional implementation, the fourth code is constructed. This helps reduce a code rate of an inner code.

In an optional implementation, the set S₄ includes a plurality of information bits; and compared with another information bit in the set S₄, when the second information bit in the set S₄ is changed to a frozen bit, an information bit that is of the second inner code and that is changed to a frozen bit has a lowest reliability rank. Based on this optional implementation, the fourth code is constructed. This helps reduce a code rate of an inner code and improve transmission reliability.

In an optional implementation, n1, n2, and n3 each are an integral power of 2.

In an optional implementation, the encoding the to-be-encoded information bit sequence based on a binary vector P₁ of a first code, to obtain an encoded bit sequence is implemented in the following manner: determining a binary vector P₇ of a seventh code based on the binary vector P₁ of the first code, where the binary vector P₇ indicates an information bit, a frozen bit, and a non-transmitted bit of the seventh code, a code length of the seventh code is n₇, a quantity of information bits of the seventh code is k₇, and a quantity of non-transmitted bits of the seventh code is n₁−n₇, k₇ is equal to the length of the to-be-encoded information bit sequence, n₇ is an integer greater than k₇,

${n_{1} = 4^{\lceil\frac{\log_{2}{(n_{7})}}{2}\rceil}},$

and k₁ is greater than or equal to k₇; encoding the to-be-encoded information bit sequence based on the binary vector P₇ of the seventh code, to obtain an encoded first bit sequence with a length of n₁; and removing the non-transmitted bit from the first bit sequence, to obtain a second bit sequence with a length of n₇; and the outputting the encoded bit sequence is implemented as: outputting the second bit sequence. Based on this optional implementation, a code with any code length can be constructed.

In an optional implementation, k₇=k₁+n₁−n₇, and the determining a binary vector P₇ of a seventh code based on the binary vector P₁ of the first code is implemented in the following manner: sequentially changing, according to a first preset rule, elements indicating information bits in P₁ to elements indicating non-transmitted bits, until a quantity of the elements indicating the non-transmitted bits in P₁ is equal to n₁−n₇, to obtain the binary vector P₇, where a value of the non-transmitted bit is independent of a value of the information bit of the seventh code. Based on this optional implementation, P₇ is determined, so that content corresponding to the information bit is not missed in the second bit sequence obtained after encoding. This helps ensure information integrity.

Optionally, the elements indicating the information bits in P₁ are sequentially changed, according to the first preset rule and based on a first binary sequence and a second binary sequence, to the elements indicating the non-transmitted bits, until the quantity of the elements indicating the non-transmitted bits in P₁ is equal to n₁−n₇, to obtain the binary vector P₇. The first binary sequence includes binary sequence numbers that are of elements in P₁ and that are arranged in descending order or in ascending order. The second binary sequence also includes binary sequence numbers of elements in P₁. The first binary sequence and the second binary sequence are permuted. Based on this optional implementation, P₇ can be accurately determined.

According to a second aspect, an embodiment provides an encoding method. The method includes: obtaining a to-be-encoded information bit sequence; encoding the to-be-coded information bit sequence based on a binary vector P₁ of a first code, to obtain an encoded bit sequence, where P₁ indicates an information bit and a frozen bit of the first code, P₁ is determined based on a target sequence and a quantity k₁ of information bits of the first code, the quantity k₁ of information bits of the first code is equal to a length of the to-be-encoded information bit sequence, a code length of the first code is n₁, the target sequence is a sequence that is extracted from a stored sequence with a length of M and that includes a sequence number less than or equal to n₁, the sequence with the length of M includes a sequence number corresponding to each of M bits, and M is greater than or equal to n₁; and outputting the encoded bit sequence. When encoding is performed in the encoding manner described in the second aspect, parallel decoding can be performed in a decoding process. This helps reduce a decoding delay.

In an optional implementation, the method further includes: determining a set S₁ from an information bit indicated by a binary vector P₂ of a second code, where when an information bit included in the set S₁ is changed to a frozen bit, at least one information bit of a first inner code can be changed to a frozen bit in a first encoding process; determining a first information bit from the set S₁; changing the first information bit in P₂ to a frozen bit, to obtain a binary vector P₃ of a third code, where a code length of the second code is M, a quantity of information bits of the second code is K, a code length of the third code is M, and a quantity of information bits of the third code is K−1; determining that a sequence number corresponding to the first information bit is K; and traversing K from M to 1, to determine a sequence number corresponding to each bit in the sequence with the length of M. Based on this optional implementation, the sequence with the length of M is generated, and encoding is performed based on the sequence with the length of M. This helps reduce a code rate of an inner code.

In an optional implementation, the set S₁ includes a plurality of information bits; and compared with another information bit in the set S₁, when the first information bit in the set S₁ is changed to a frozen bit, an information bit that is of the first inner code and that is changed to a frozen bit has a lowest reliability rank. Based on this optional implementation, the sequence with the length of M is generated, and encoding is performed based on the sequence with the length of M. This helps reduce a code rate of an inner code and improve transmission reliability.

According to a third aspect, a communications device is provided. The communications device may perform the method according to any one of the first aspect, the second aspect, the optional implementations of the first aspect, or the optional implementations of the second aspect. The function may be implemented by hardware or may be implemented by hardware executing corresponding software. The hardware or the software includes one or more units corresponding to the foregoing function. The unit may be software and/or hardware. Based on a same inventive concept, for a problem-resolving principle and beneficial effects of the communications device, refer to the problem-resolving principle and the beneficial effects of the method according to any one of the first aspect, the second aspect, the optional implementations of the first aspect, or the optional implementations of the second aspect. Repeated parts are not described in detail again.

According to a fourth aspect, a communications device is provided. The communications device includes a processor, a memory, and a communications interface. The processor, the communications interface, and the memory are connected. The communications interface may be a transceiver. The communications interface is configured to implement communication between the communications device and another network element. One or more programs are stored in the memory. The processor invokes the program stored in the memory, to implement the method according to any one of the first aspect, the second aspect, the optional implementations of the first aspect, or the optional implementations of the second aspect. For a problem-resolving implementation and beneficial effects of the communications device, refer to the problem-resolving implementation and the beneficial effects of the method according to any one of the first aspect, the second aspect, the optional implementations of the first aspect, or the optional implementations of the second aspect. Repeated parts are not described in detail again.

According to a fifth aspect, a computer program product is provided. When the computer program product runs on a computer, the computer is enabled to perform the method according to any one of the first aspect, the second aspect, the optional implementations of the first aspect, or the optional implementations of the second aspect.

According to a sixth aspect, a chip product is provided, to perform the method according to any one of the first aspect, the second aspect, the optional implementations of the first aspect, or the optional implementations of the second aspect.

According to a seventh aspect, a computer-readable storage medium is provided. The computer-readable storage medium stores instructions. When the instructions are run on a computer, the computer is enabled to perform the method according to any one of the first aspect, the second aspect, the optional implementations of the first aspect, or the optional implementations of the second aspect.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of an existing communication procedure;

FIG. 2 is a schematic diagram of a trellis graph according to an embodiment;

FIG. 3 is a schematic flowchart of an encoding method according to an embodiment;

FIG. 4 is a schematic diagram of another trellis graph according to an embodiment;

FIG. 5 is a schematic diagram of still another trellis graph according to an embodiment;

FIG. 6 is a schematic structural diagram of a communications device according to an embodiment;

FIG. 7 is a schematic structural diagram of a communications device according to an embodiment;

FIG. 8 is a schematic flowchart of another encoding method according to an embodiment;

FIG. 9 is a schematic diagram of a first binary sequence and a second binary sequence according to an embodiment;

FIG. 10 is a schematic diagram of still another trellis graph according to an embodiment; and

FIG. 11 is a schematic diagram of still another trellis graph according to an embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The following further describes the specific embodiments in detail with reference to the accompanying drawings.

The embodiments provide an encoding method and a communications device, to help reduce a decoding delay.

The solutions in the embodiments are applicable to various communications systems, for example, a 5G communications system, a global system for mobile communications (GSM) system, a code division multiple access (CDMA) system, a wideband code division multiple access (WCDMA) system, a general packet radio service (GPRS) system, a long term evolution (LTE) system, an LTE frequency division duplex (FDD) system, an LTE time division duplex (TDD) system, and a universal mobile telecommunications system (UMTS).

FIG. 1 shows a basic communication procedure performed by using a wireless technology. As shown in FIG. 1, before sending information, a communications device needs to perform source encoding on to-be-sent information, performs channel encoding on information obtained after source encoding, and then sends information obtained after channel encoding. After receiving the information obtained after channel encoding, a receiver end first performs channel decoding on the information obtained after channel encoding, then performs source decoding on information obtained after channel decoding, and finally obtains the information sent by the transmitter end. Channel encoding is critical to reliability of information transmission in an entire communications system.

A channel encoding process is c^(N)=u^(N)F_(N), where u^(N)=(u₁,u₂,K,u_(N)) is a binary row vector, u^(N) is a to-be-encoded bit vector with a length of N (namely a code length), F_(N) is an N×N matrix, and F_(N)=F₂ ^(⊗(log) ² ^((N))). Herein,

${F_{2} = \begin{bmatrix} 1 & 0 \\ 1 & 1 \end{bmatrix}},$

where F₂ ^(⊗(log) ² ^((N))) is defined as a Kronecker product of log₂ N matrices F₂, and ⊗ represents an operator of the Kronecker product. The foregoing related addition and multiplication operations are all addition and multiplication operations in a binary Galois field.

Some bits in u^(N) are used to carry information and are referred to as information bits. Some other bits are used to carry fixed values pre-agreed upon by the transmitter end and the receiver end and are referred to as fixed bits or frozen bits. The frozen bit is used for description in the following parts. For example, a value carried in a frozen bit is usually 0. Before encoding is performed, the information bits used to carry information in u^(N) need to be determined, that is, locations at which bits are used to carry information in u^(N) need to be determined. A process of determining the information bits used to carry information in u^(N) is referred to as construction of a code.

For example, a trellis graph is used to describe the channel encoding process. FIG. 2 shows a trellis graph indicating a channel encoding process. As shown in FIG. 2, in the trellis graph, u¹⁶=(u₁,u₂,K,u₁₆), and c¹⁶=(c₁,c₂,K,c₁₆). In to-be-encoded bit vectors (u₁,u₂,K,u₁₆), u₆, u₇, u₈, u₁₀, u₁₁, u₁₂, u₁₄, u₁₅, and u₁₆ are information bits in which information is filled, and u₁ to u₅, u₉, and u₁₃ are frozen bits in which fixed values, for example, 0, pre-agreed upon by the transmitter end and the receiver end are filled. For example, in FIG. 2, solid nodes corresponding to u₁ to u₁₆ represent the information bits, and hollow nodes represent the frozen bits. Before performing encoding, a communications device first needs to determine an information bit and a frozen bit in u¹⁶, that is, determine the information bit and the frozen bit in u¹⁶. Then, the information bit in u¹⁶ is filled with information in a received to-be-encoded information bit sequence, and the frozen bit in u¹⁶ is filled with a fixed value, for example, 0, pre-agreed upon by the transmitter end and the receiver end. Then, the communications device encodes u¹⁶ in which the information and the fixed values are filled, and finally obtains an encoded bit sequence c¹⁶.

The communications device may be an access network device or a terminal device. Alternatively, the communications device may be another device that needs to perform channel encoding. This is not limited in this embodiment.

The access network device may provide communication coverage for a specific geographical area and may communicate with a terminal device located in the coverage area. The access network device may support communication protocols of different standards or may support different communication modes. For example, the access network device may be an evolved NodeB (eNB, or eNodeB) in an LTE system or a radio network controller in a cloud radio access network (CRAN), may be an access network device in a 5G network, such as a gNB, may be a small cell, a micro cell, or a transmission reception point (TRP), or may be a relay station, an access point, an access network device in a future evolved public land mobile network (PLMN), or various forms of devices that perform a function of a base station in the future.

The terminal device may be an access terminal, user equipment (UE), a subscriber unit, a subscriber station, a mobile station, a mobile platform, a remote station, a remote terminal, a mobile terminal, a user terminal, a terminal, a wireless communications device, a user agent, a user apparatus, or the like. The access terminal may be a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a handheld device having a wireless communication function, a computing device, another processing device connected to a wireless modem, a vehicle-mounted device, a wearable device, a terminal device in the internet of things, a virtual reality device, a terminal device in a 5G network or a future communications network, a terminal device in a future evolved public land mobile network (PLMN), or the like.

The following further describes an encoding method and a communications device that are provided in the embodiments.

FIG. 3 is a schematic flowchart of an encoding method according to an embodiment. As shown in FIG. 3, the encoding method includes the following steps 301 to 303.

301: A communications device obtains a to-be-encoded information bit sequence.

302: The communications device encodes the to-be-encoded information bit sequence based on a binary vector P₁ of a first code, to obtain an encoded bit sequence.

P₁ is determined based on a binary vector P₂ of a second code and a binary vector P₃ of a third code. P₁ indicates an information bit and a frozen bit of the first code, P₂ indicates an information bit and a frozen bit of the second code, and P₃ indicates an information bit and a frozen bit of the third code. A code length of the first code is n₃, and a quantity of information bits of the first code is k₁. A code length of the second code is n₂, and a quantity of information bits of the second code is k₂. A code length of the third code is n₃, and a quantity of information bits of the third code is k₃. n₁=n₂*n₃, and k₁=k₂*k₃.

P₁ may be represented as P₁=[p_(1,1),p_(1,2), . . . , p_(1,n) ₁ ], P₂ may be represented as P₂=[p_(2,1),p_(2,2), . . . , p_(2,n) ₂ ], and P₃ may be represented as P₃=[p_(3,1), p_(3,2), . . . , p_(3,n) ₃ ]. Optionally, when p_(1,z)=0, it indicates that a z^(th) bit of the first code is a frozen bit. When p_(1,z)=1, it indicates that a z^(th) bit of the first code is an information bit. When p_(2,z)=0, it indicates that a z^(th) bit of the second code is a frozen bit. When p_(2,z)=1, it indicates that a z^(th) bit of the second code is an information bit. When p_(3,z)=0, it indicates that a z^(th) bit of the third code is a frozen bit. When P_(3,z)=1, it indicates that a z^(th) bit of the third code is an information bit.

For example, the first code is a (32, 4) code of. For example, the code length n₁ of the first code is 32, the quantity k₁ of information bits is 4, and P₁=[00000000000000000000000000110011]. P₁ indicates that the 1^(st) bit to the 26^(th) bit, the 29^(th) bit, and the 30^(th) bit of the first code are frozen bits, and the 27^(th) bit, the 28^(th) bit, the 31^(st) bit, and the 32^(nd) bit of the first code are information bits. The second code is an (8, 2) code of. For example, the code length n₂ of the second code is 8, the quantity k₂ of information bits is 2, and P₂=[00000011]. P2 indicates that the 1^(st) bit to the 6^(th) bit of the second code are frozen bits, and the 7^(th) bit and the 8^(th) bit of the second code are information bits. The third code is a (4, 2) code. For example, the code length n₃ of the third code is 4, the quantity k₃ of information bits is 2, and P₃=[0011]. P3 indicates that the 1^(st) bit and the 2^(nd) bit of the third code are frozen bits, and the 3^(rd) bit and the 4^(th) bit of the third code are information bits.

Alternatively, when p_(1,z)=1, it indicates that a z^(th) bit of the first code is a frozen bit. When P_(1,z)=0, it indicates that a z^(th) bit of the first code is an information bit. When p_(1,z)=1, it indicates that a z^(th) bit of the second code is a frozen bit. When p_(2,z)=0, it indicates that a z^(th) bit of the second code is an information bit. When p_(3,z)=1, it indicates that a z^(th) bit of the third code is a frozen bit. When p_(3,z)=0, it indicates that a z^(th) bit of the third code is an information bit.

For example, the first code is a (32, 4) code, and P₁=[11111111111111111111111111001100]. P₁ indicates that the 1^(st) bit to the 26^(th) bit, the 29^(th) bit, and the 30^(th) bit of the first code are frozen bits, and the 27^(th) bit, the 28^(th) bit, the 31^(st) bit, and the 32^(nd) bit of the first code are information bits. The second code is an (8, 2) code, and P₂=[11111100]. P2 indicates that the 1^(st) bit to the 6^(th) bit of the second code are frozen bits, and the 7^(th) bit and the 8^(th) bit of the second code are information bits. The third code is a (4, 2) code, and P₃=[1100]. P3 indicates that the 1^(st) bit and the 2^(nd) bit of the third code are frozen bits, and the 3^(rd) bit and the 4^(th) bit of the third code are information bits.

For ease of description, in the following embodiments, that P₁, P₂, P₃, P₄, P₅, P₆, and P₇ each indicate an information bit and a frozen bit in a first manner is used as an example for description. For example, 0 indicates that a corresponding bit is a frozen bit, and 1 indicates that a corresponding bit is an information bit.

Optionally, n₁, n₂, and n₃ each are an integral power of 2. For example, n₁ is 16, n₂ is 8, and n₃ is 2. Alternatively, n₁ is 32, n₂ is 8, and n₃ is 4. Alternatively, m is 64, n₂ is 16, and n₃ is 4.

Optionally, n₁, n₂, and n₃ each may not be an integral power of 2. For example, m is 72, n₂ is 12, and n₃ is 6. Alternatively, n₁ is 60, n₂ is 10, and n₃ is 6.

Optionally, n₂ is different from n₃, and k₂ is different from k₃. For example, the first code may be a (32, 8) code. For example, the code length m of the first code is 32, and the quantity k₁ of information bits is 8. The second code may be an (8, 4) code. For example, the code length n₂ of the second code is 8, and the quantity k₂ of information bits is 4. The third code may be a (4, 2) code. For example, the code length n₃ of the third code is 4, and the quantity k₃ of information bits is 2.

Optionally, n₂ is the same as n₃, and k₂ is different from k₃. For example, the first code may be a (64, 8) code. For example, the code length m of the first code is 64, and the quantity k₁ of information bits is 8. The second code may be an (8, 4) code. For example, the code length n₂ of the second code is 8, and the quantity k₂ of information bits is 4. The third code may be an (8, 2) code. For example, the code length n₃ of the third code is 8, and the quantity k₃ of information bits is 2.

Optionally, n₂ is different from n₃, and k₂ is the same as k₃. For example, the first code may be a (128, 16) code. For example, the code length m of the first code is 128, and the quantity k₁ of information bits is 16. The second code may be an (8, 4) code. For example, the code length n₂ of the second code is 8, and the quantity k₂ of information bits is 4. The third code may be a (16, 4) code. For example, the code length n₃ of the third code is 16, and the quantity k₃ of information bits is 4.

Optionally, n₂ is the same as n₃, and k₂ is the same as k₃. For example, the first code may be a (64, 16) code. For example, the code length m of the first code is 64, and the quantity k₁ of information bits is 16. The second code may be an (8, 4) code. For example, the code length n₂ of the second code is 8, and the quantity k₂ of information bits is 4. The third code may be an (8, 4) code. For example, the code length n₃ of the third code is 8, and the quantity k₃ of information bits is 4.

In an optional implementation, after the communications device receives the to-be-encoded information bit sequence, the communications device determines the code length n₂ and the quantity k₂ of information bits of the second code, and the code length n₃ and the quantity k₃ of information bits of the third code based on the code length n₁ and the quantity k₁ of information bits of the first code. After determining the code length n₂ and the quantity k₂ of information bits of the second code and the code length n₃ and the quantity k₃ of information bits of the third code, the communications device determines the binary vector P₂ of the second code and the binary vector P₃ of the third code. Then, the communications device determines P₁ based on P₂ and P₃. After determining P₁, the communications device may encode the to-be-encoded information bit sequence based on P₁, to obtain the encoded bit sequence.

Alternatively, the code length and the quantity of information bits of the second code and the code length and the quantity of information bits of the third code may be preset. After receiving the to-be-encoded information bit sequence, the communications device does not need to determine the code length n₂ and the quantity k₂ of information bits of the second code and the code length n₃ and the quantity k₃ of information bits of the third code based on the code length m and the quantity k₁ of information bits of the first code. After receiving the to-be-encoded information bit sequence, the communications device may directly determine P₂ of the second code and P₃ of the third code, then determine P₁ based on P₂ and P₃, and encode the to-be-encoded information bit sequence based on P₁, to obtain the encoded bit sequence.

Optionally, the second code and the third code may be polar codes. P₂ of the second code and P₃ of the third code may be determined by using an existing polar code construction method. For example, P₂ of the second code and P₃ of the third code may be determined by using a method such as Gaussian approximation (GA), density evolution (DE), PW, or NR.

For example, P₂ is determined by using the GA method or the DE method. When determining P₂ of the (8, 2) second code, the communications device determines a subchannel capacity corresponding to each bit of the second code and selects a bit corresponding to a relatively large subchannel capacity as an information bit. For example, if subchannel capacities corresponding to the 7^(th) bit and the 8^(th) bit of the second code are relatively large, the communications device determines the 7^(th) bit and the 8^(th) bit as information bits. For example, when p_(2,z)=0, it indicates that a z^(th) bit of the second code is a frozen bit; or when p_(2,z)=1, it indicates that a z^(th) bit of the second code is an information bit; and P₂=[00000011]. The same principle is used to determine P₃ of the third code. Details are not described herein again.

For another example, P₂ is determined by using the PW method or the NR method. When determining P₂ of the (8, 2) second code, the communications device samples, from a PW sequence, an NR sequence, or another pre-stored sequence, a location at which a sequence element is less than or equal to 8, to obtain a sequence [8, 7, 6, 4, 5, 3, 2, 1] with a length of 8. The sequence represents a subchannel reliability rank corresponding to each bit of the second code. For example, a subchannel reliability rank corresponding to the 1^(st) bit of the second code is 8, a subchannel reliability rank corresponding to the 2^(nd) bit of the second code is 7, a subchannel reliability rank corresponding to the 3^(rd) bit of the second code is 6, a subchannel reliability rank corresponding to the 4^(th) bit of the second code is 4, a subchannel reliability rank corresponding to the 5^(th) bit of the second code is 5, a subchannel reliability rank corresponding to the 6^(th) bit of the second code is 3, a subchannel reliability rank corresponding to the 7^(th) bit of the second code is 2, and a subchannel reliability rank corresponding to the 8^(th) bit of the second code is 1. Based on the sequence, the communications device may determine a bit that is of the second code and that corresponds to relatively high subchannel reliability as an information bit. For example, if channel reliability of subchannels corresponding to the 7^(th) bit and the 8^(th) bit of the second code is highest, the communications device determines the 7^(th) bit and the 8^(th) bit of the second code as information bits. For example, when p_(2,z)=0, it indicates that a z^(th) bit of the second code is a frozen bit; or when P_(2,z)=1, it indicates that a z^(th) bit of the second code is an information bit; and P₂=[00000011] is obtained. The same principle is used to determine P₃ of the third code. Details are not described herein again.

In an optional implementation, P₁=P₂⊗P₃. After determining P₂ and P₃, the communications device may perform a Kronecker product operation on P₂ and P₃, to obtain the binary vector P₁ of the first code.

For example, P₂=[00000011], P₃=[0011], and P₁=P₂⊗P₃=[00000000000000000000000000110011].

In an optional implementation, when n₂=n₃ and k₂=k₃, P₂ is equal to P₃.

For example, the first code is a (16, 9) code, the second code is a (4, 3) code, and the third code is a (4, 3) code. P₂=P₃=[0111], and P₁=P₂⊗P₃=[0000011101110111].

In an optional implementation, when n₂=n₃ and k₂=k₃, P₂ may alternatively not be equal to P₃. For example, although P₂ and P₃ have the same length, values in P₂ and P₃ are different.

In this embodiment, k₁=k₄, or k₄<k₁, where k₄ is a length of the to-be-encoded information bit sequence. A specific implementation in which the communications device encodes the to-be-encoded information bit sequence based on the binary vector P₁ of the first code when k₁=k₄ is different from a specific implementation in which the communications device encodes the to-be-encoded information bit sequence based on the binary vector P₁ of the first code when k₄<k₁. The following separately describes scenarios k₁=k₄ and k₄<k₁ in detail.

1. Scenario k₁=k₄: In this scenario, the quantity of information bits of the first code is equal to the length of the to-be-encoded information bit sequence. After determining P₁ of the first code, the communications device can directly fill the information bit of the first code with information in the to-be-encoded information bit sequence, and fill the frozen bit of the first code with a fixed value, for example, 0. After filling the first code with the information and the fixed value, the communications device obtains u^(n) ^(l) , and then encodes u^(n) ^(l) , to obtain c^(n) ^(l) , where c^(n) ^(l) =u^(n) _(l)F_(n) _(l) .

For example, the communications device receives the to-be-encoded information bit sequence. The length k₄ of the to-be-encoded information bit sequence is 4. After receiving the to-be-encoded information bit sequence, the communications device determines, based on the to-be-encoded information bit sequence, that the quantity k₁ of information bits of the first code is 4. The code length m of the first code may be preset, for example, may be 32. Alternatively, both the quantity k₁ of information bits and the code length m of the first code are preset, the quantity k₁ of information bits of the first code is 4, and the code length n₁ of the first code is 32.

The communications device factorizes the code length n₃ and the quantity k₁ of information bits of the (32, 4) first code, to obtain the code length n₂ and the quantity k₂ of information bits of the second code and the code length n₃ and the quantity k₃ of information bits of the third code, n₁=*n₃, and k₁=k₂*k₃. For example, the following is obtained: n₂ is 8, k₂ is 2, n₃ is 4, and k₃ is 2. For example, the second code is an (8, 2) code, and the third code is a (4, 2) code.

The communications device determines the binary vector P₂=[00000011] of the second code and the binary vector P₃=[0011] of the third code by using the GA, DE, PW, or NR method. After determining P₂ and P₃, the communications device performs a Kronecker product operation on P₂ and P₃, to obtain the binary vector P₁ of the first code, that is, P₁=P₂ ⊗P₃=[00000000000000000000000000110011]. For example, P₁ indicates that the 1^(st) bit to the 26^(th) bit, the 29^(th) bit, and the 30^(th) bit of the first code are frozen bits, and the 27^(th) bit, the 28^(th) 10 bit, the 31^(st) bit, and the 32^(nd) bit of the first code are information bits. The communications device fills the 1^(st) bit to the 26^(th) bit, the 29^(th) bit, and the 30^(th) bit of the first code with fixed values, for example, 0. The communications device fills the 27^(th) bit, the 28^(th) bit, the 31^(st) bit, and the 32^(nd) bit of the first code with bit values in the to-be-encoded information bit sequence. After filling all the bits of the first code with values, the communications device obtains u³². Then, the communications device encodes u³², to obtain c³², where c³²=u³²F₃₂.

For another example, the communications device receives the to-be-encoded information bit sequence. The length k₄ of the to-be-encoded information bit sequence is 9. After receiving the to-be-encoded information bit sequence, the communications device determines, based on the to-be-encoded information bit sequence, that the quantity k₁ of information bits of the first code is 9. The code length m of the first code may be preset, for example, may be 16. Alternatively, both the quantity k₁ of information bits and the code length m of the first code are preset, the quantity k₁ of information bits of the first code is 9, and the code length m of the first code is 16.

The communications device factorizes the code length m and the quantity k₁ of information bits of the (16, 9) first code, to obtain the code length n₂ and the quantity k₂ of information bits of the second code and the code length n₃ and the quantity k₃ of information bits of the third code, n₁=n₂*n₃, and k₁=k₂*k₃. For example, the following is obtained: n₂ is 4, k₂ is 3, n₃ is 4, and k₃ is 3. For example, the second code is a (4, 3) code, and the third code is a (4, 3) code.

The communications device determines the binary vector P₂=[0111] of the second code and the binary vector P₃=[0111] of the third code by using the GA, DE, PW, or NR method. After determining P₂ and P₃, the communications device performs a Kronecker product operation on P₂ and P₃, to obtain the binary vector P₁ of the first code, that is, P₁=P₂ ⊗P₃=[0000011101110111]. For example, P₁ indicates that the 1^(st) bit to the 5^(th) bit, the 9^(th) bit, and the 13^(th) bit of the first code are frozen bits, and the 6^(th) bit to the 8^(th) bit, the 10^(th) bit to the 12^(th) bit, and the 14^(th) bit to the 16^(th) bit of the first code are information bits. The communications device fills the 1^(st) bit to the 5^(th) bit, the 9^(th) bit, and the 13^(th) bit of the first code with fixed values, for example, 0. The communications device fills the 6^(th) bit to the 8^(th) bit, the 10^(th) bit to the 12^(th) bit, and the 14^(th) bit to the 16^(th) bit of the first code with bit values in the to-be-encoded information bit sequence. After filling all the bits of the first code with values, the communications device obtains u¹⁶. Then, the communications device encodes u¹⁶, to obtain c¹⁶, where c¹⁶=u¹⁶F₁₆.

2. Scenario k₄<k₁: In this scenario, k₁=┌√{square root over (k₄)}┐², where k₄ is the length of the to-be-encoded information bit sequence. For example, k₄ is equal to 3, and k₁ is equal to 4; or k₄ is equal to 5, and k₁ is equal to 9.

In an optional implementation, that the communications device encodes the to-be-encoded information bit sequence based on a binary vector P₁ of a first code is implemented in the following manner: The communications device determines, based on P₁, a binary vector P₄ corresponding to a fourth code, where P₄ indicates an information bit and a frozen bit of the fourth code, a code length of the fourth code is n₄, a quantity of information bits of the fourth code is k₄, and n₄=n₁; and the communications device encodes the to-be-encoded information bit sequence based on P₄.

Optionally, after receiving the to-be-encoded information bit sequence, the communications device may first determine the quantity of information bits of the fourth code, where the quantity of information bits of the fourth code is equal to the length of the to-be-encoded information bit sequence. After determining the quantity of information bits of the fourth code, the communications device determines the code length and the quantity of information bits of the first code based on the code length and the quantity of information bits of the fourth code, where the code length of the fourth code may be preset. After determining the code length and the quantity of information bits of the first code, the communications device determines the code length and the quantity of information bits of the second code and the code length and the quantity of information bits of the third code based on the code length and the quantity of information bits of the first code. After determining the code length and the quantity of information bits of the second code and the code length and the quantity of information bits of the third code, the communications device determines P₂ of the second code and P₃ of the third code, and then determines P₁ based on P₂ and P₃. After determining P₁, the communications device determines P₄ based on P₁, and then encodes the to-be-encoded information bit sequence based on P₄.

For example, the communications device receives the to-be-encoded information bit sequence. The length k₄ of the to-be-encoded information bit sequence is 6. The communications device determines, based on the length of the to-be-encoded information bit sequence, that the quantity of information bits of the fourth code is k₄, that is, 6. The communications device determines the code length n₃ and the quantity k₁ of information bits of the first code based on the code length n₄ and the quantity k₄ of information bits of the fourth code. The code length of the fourth code may be preset. For example, n₄ may be 16. Therefore, the fourth code is a (16, 6) code. Because n₄ is equal to n₃, and k₁=┌√{square root over (k₄)}┐², the code length n₁ of the first code is equal to 16, and the quantity k₁ of information bits of the first code is equal to 9. For example, the first code is a (16, 9) code.

The communications device factorizes the code length n₃ and the quantity k₁ of information bits of the (16, 9) first code, to obtain the code length n₂ and the quantity k₂ of information bits of the second code and the code length n₃ and the quantity k₃ of information bits of the third code, n₁=n₂*n₃, and k₁=k₂*k₃. Therefore, n₂ may be 4, k₂ may be 3, n₃ may be 4, and k₃ may be 3. For example, the second code is a (4, 3) code, and the third code is a (4, 3) code. The communications device determines the binary vector P₂=[0111] of the second code and the binary vector P₃=[0111] of the third code by using the GA, DE, PW, or NR method. After determining P₂ and P₃, the communications device performs a Kronecker product operation on P₂ and P₃, to obtain the binary vector P₁ of the first code, that is, P₁=P₂⊗P₃=[0000011101110111]. After determining P₁, the communications device determines P₄ of the (16, 6) fourth code based on P₁, and then encodes the to-be-encoded information bit sequence based on P₄. For example, P₄=[0000001001110011]. P₄ indicates that the 1^(st) bit to the 6^(th) bit, the 8^(th) bit, the 9^(th) bit, the 13^(th) bit, and the 14^(th) bit of the fourth code are frozen bits, and the 7^(th) bit, the 10^(th) bit to the 12^(th) bit, the 15^(th) bit, and the 16^(th) bit of the fourth code are information bits. The communications device fills the 1^(st) bit to the 6^(th) bit, the 8^(th) bit, the 9^(th) bit, the 13^(th) bit, and the 14^(th) bit of the fourth code with fixed values, for example, 0. The communications device fills the 7^(th) bit, the 10^(th) bit to the 12^(th) bit, the 15^(th) bit, and the 16^(th) bit of the fourth code with bit values in the to-be-encoded information bit sequence. After filling all the bits of the fourth code with values, the communications device obtains u¹⁶. Then, the communications device encodes u¹⁶, to obtain c¹⁶, where c¹⁶=u¹⁶F₁₆.

In an optional implementation, a set S₂ is a subset of a set S₁, the set S₁ is an information bit set including the information bit indicated by P₁, and S₂ is an information bit set including the information bit indicated by P₄.

For example, P₁=[0000011101110111], and P₄=[0000001001110011]. P₁ indicates that the 1^(st) bit to the 5^(th) bit, the 9^(th) bit, and the 13^(th) bit of the first code are frozen bits, and the 6^(th) bit to the 8^(th) bit, the 10^(th) bit to the 12^(th) bit, and the 14^(th) bit to the 16^(th) bit of the first code are information bits. Therefore, the set S₁ includes the information bits: the 6^(th) bit to the 8^(th) bit, the 10^(th) bit to the 12^(th) bit, and the 14^(th) bit to the 16^(th) bit, that is, S₁=[u₆,u₇,u₈,u₉,u₁₀,u₁₁,u₁₂,u₁₄,u₁₅,u₁₆].

P₄ indicates that the 1^(st) bit to the 6^(th) bit, the 8^(th) bit, the 9^(th) bit, the 13^(th) bit, and the 14^(th) bit of the fourth code are frozen bits, and the 7^(th) bit, the 10^(th) bit to the 12^(th) bit, the 15^(th) bit, and the 16^(th) bit of the fourth code are information bits. Therefore, the set S₂ includes the information bits: the 7^(th) bit, the 10^(th) bit to the 12^(th) bit, the 15^(th) bit, and the 16^(th) bit, that is, S₂=[u₇,u₁₀,u₁₁,u₁₂,u₁₅,u₁₆]. It can be understood that the information bits in the set S₁ include the information bits in the set S₂.

In an optional implementation, that the communications device determines, based on P₁, a binary vector P₄ corresponding to a fourth code is implemented in the following manner: determining a set S₃ from the set S₁, where when an information bit included in the set S₃ is changed to a frozen bit, at least one information bit of a first inner code can be changed to a frozen bit in a first encoding process; determining a first information bit from the set S₃; changing the first information bit in P₁ to a frozen bit, to obtain a binary vector P₅; and obtaining the binary vector P₄ corresponding to the fourth code based on the binary vector P₅.

For example, the communications device receives the to-be-encoded information bit sequence. The length k₄ of the to-be-encoded information bit sequence is 6. The fourth code is a (16, 6) code, and the first code is a (16, 9) code. P₁ of the first code is P₁=[0000011101110111], and S₁=[u₆,u₇,u₈,u₁₀,u₁₁,u₁₂,u₁₄,u₁₅,u₁₆].

For ease of description, a specific manner of determining the set S₃ from the set S₁ is described below with reference to a corresponding trellis graph. For encoding with a code length of n₁, a trellis graph corresponding to the encoding has a total of log₂(n₁) layers. For a trellis graph shown in FIG. 4, an operation on the first ½*log₂ n₁ orders of the trellis graph is used as a first outer code, and an operation on the last ½*log₂ n₁ orders is used as a first inner code. Because n₁ is equal to 16, for the trellis graph shown in FIG. 4, an operation on the first 2 orders is used as the first outer code, and an operation on the last 2 orders is used as the first inner code. An encoding process indicated by the trellis graph shown in FIG. 4 is a first encoding process.

As shown in FIG. 4, bits [u₅, u₆, u₇, u₈, u₉, u₁₀, u₁₁, u₁₂, u₁₃, u₁₄, u₁₅, u₁₆] of the first code respectively correspond to codeword bits [x₅, x₆, x₇, x₈, x₉, x₁₀, x₁₁, x₁₂, x₁₃, x₁₄, x₁₅, x₁₆] of the first outer code. The codeword bits [x₅, x₆, x₇, x₈] of the first outer code meet the following relationship:

$\left\{ \begin{matrix} {x_{5} = {u_{5} \oplus u_{6} \oplus u_{7} \oplus u_{8}}} \\ {x_{6} = {u_{6} \oplus u_{8}}} \\ {x_{7} = {u_{7} \oplus u_{8}}} \\ {x_{8} = u_{8}} \end{matrix} \right..$

It can be understood that if the information bit u₈ is changed to a frozen bit, the information bit x₈ of the first inner code is also changed to a frozen bit. When the information bit x₈ of the first inner code is changed to the frozen bit, a code rate of the inner code is reduced. Likewise, x₉, x₁₀, x₁₁, x₁₂, x₁₃, x₁₄, x₁₅, and x₁₆ also meet a relationship. Details are not described herein again. In the embodiments, only codeword bits [x₅, x₆, x₇, x₈] of the first outer code are used as an example for description.

Therefore, an information bit that is in the S₁ and that enables an information bit of the first inner code to be changed to a frozen bit when the information bit is changed to a frozen bit can be determined by sequentially traversing the information bits in the set S₁. According to the foregoing method, after the information bits in the set S₁ are traversed, the following can be determined: when u₈ is changed to a frozen bit, the information bit x₈ of the first inner code can be changed to a frozen bit. When u₁₂ is changed to a frozen bit, the information bit x₁₂ of the first inner code can be changed to a frozen bit. When u₁₆ is changed to a frozen bit, the information bit x₁₆ of the first inner code can be changed to a frozen bit. Therefore, the communications device determines that S₃=[u₈, u₁₂, u₁₆].

After determining the set S₃, the communications device may select a first information bit from the set S₃, change the first information bit in P₁ to a frozen bit, to obtain P₅, and then determine P₄ based on P₅. For example, if the first information bit is u₈, P₅=[0000011001110111], and the communications device determines P₄ based on P₅=[0000011001110111].

If the set S₃ includes a plurality of information bits, the first information bit may be any information bit in the set S₃. For example, if S₃=[u₈, u₁₂, u₁₆], the first information bit may be u₈, u₁₂, or u₁₆.

Alternatively, the set S₃ includes a plurality of information bits; and compared with another information bit in the set S₃, when the first information bit in the set S₃ is changed to a frozen bit, an information bit that is of the first inner code and that is changed to a frozen bit has a lowest reliability rank. For example, when S₃=[u₈, u₁₂, u₁₆], and u₈ is changed to a frozen bit, the information bit x₈ of the first inner code is changed to a frozen bit; when u₁₂ is changed to a frozen bit, the information bit x₁₂ of the first inner code is changed to a frozen bit; and when u₁₆ is changed to a frozen bit, the information bit x₁₆ of the first inner code is changed to a frozen bit. Reliability of x₈ is lower than reliability of x₁₂, and the reliability of x₁₂ is less than reliability of x₁₆. Therefore, the communications device determines that u₈ is the first information bit.

If the set S₃ includes only one information bit, the information bit is the first information bit.

It should be noted that if the fourth code is a (16, 8) code, and the first code is a (16, 9) code, P₅=[0000011001110111]. A quantity of information bits in P₅ is equal to the quantity k₄ of information bits of the fourth code. In this case, the communications device may directly determine P₅ as P₄, and then encode the to-be-encoded information bit sequence based on P₄.

In an optional implementation, if the quantity of information bits in P₅ is greater than the quantity k₄ of information bits of the fourth code, that the communications device obtains the binary vector P₄ corresponding to the fourth code based on the binary vector P₅ is implemented in the following manner: determining a set S₄ from an information bit indicated by P₅, where when an information bit included in the set S₄ is changed to a frozen bit, at least one information bit of a second inner code can be changed to a frozen bit in a second encoding process, the first inner code is an outer code for the second encoding process, and the second inner code is an outer code for the first encoding process; determining a second information bit from the set S₄; changing the second information bit in P₅ to a frozen bit, to obtain a binary vector P₆; and obtaining the binary vector P₄ corresponding to the fourth code based on the binary vector P₆.

For example, the fourth code is a (16, 6) code, and P₅=[0000011001110111]. For example, the quantity of information bits in P₅ is 8, the quantity k₄ of information bits of the fourth code is 6, and the quantity of information bits in P₅ is greater than k₄. The communications device determines the set S₄ from the information bits indicated by P₅=[0000011001110111], The information bits indicated by P₅ include [u₆, u₇, u₁₀, u₁₁, u₁₂, u₁₄, u₁₅, u₁₆]. For ease of description, a specific manner of determining the set S₄ is described below with reference to a corresponding trellis graph. An encoding process indicated by a trellis graph shown in FIG. 5 is a second encoding process. The first outer code in the trellis graph shown in FIG. 4 is a second inner code in the trellis graph shown in FIG. 5, and the first inner code in the trellis graph shown in FIG. 4 is a second outer code in the trellis graph shown in FIG. 5.

A principle for determining the set S₄ from the information bit indicated by P₅ is similar to a principle for determining the set S₃ from the information bit indicated by P₁. As shown in FIG. 5, if u₁₄ is changed to a frozen bit, an information bit x₁₄ of the second inner code can be changed to a frozen bit in the second encoding process; if u₁₅ is changed to a frozen bit, the information bit x₁₅ of the second inner code can be changed to a frozen bit in the second encoding process; and if u₁₆ is changed to a frozen bit, the information bit x₁₆ of the second inner code can be changed to a frozen bit in the second encoding process. Therefore, the communications device may determine that S₄=[u₁₄, u₁₅, u₁₆].

After determining the set S₄, the communications device may select a second information bit from the set S₄, change the second information bit in P₅ to a frozen bit, to obtain P₆, and then determine P₄ based on P₆. For example, if the second information bit is u₁₄, P₆=[0000011001110011], and the communications device determines P₄ based on P₆.

If the set S₄ includes a plurality of information bits, the second information bit may be any information bit in the set S₄. For example, if S₄=[u₁₄, u₁₅, u₁₆], the second information bit may be u₁₄, u₁₅, or u₁₆.

Alternatively, the set S₄ includes a plurality of information bits; and compared with another information bit in the set S₄, when the second information bit in the set S₄ is changed to a frozen bit, an information bit that is of the second inner code and that is changed to a frozen bit has a lowest reliability rank. For example, when S₄=[u₁₄, u₁₅, u₁₆], and u₁₄ is changed to a frozen bit, the information bit x₁₄ of the second inner code is changed to a frozen bit; when u₁₅ is changed to a frozen bit, the information bit x₁₅ of the second inner code is changed to a frozen bit; and when u₁₆ is changed to a frozen bit, the information bit x₁₆ of the second inner code is changed to a frozen bit. Reliability of x₁₄ is lower than reliability of x₁₅, and the reliability of x₁₅ is less than reliability of x₁₆. Therefore, the communications device determines that u₁₄ is the second information bit. If the set S₄ includes only one information bit, the information bit is the second information bit.

Because the quantity of information bits of the fourth code is 6, one information bit further needs to be selected from P₆=[0000011001110011] and changed to a frozen bit. The communications device may determine, according to a principle the same as the principle for determining the set S₃, a set S₅ from an information bit indicated by P₆. For example, S₅=[u₆, u₇, u₁₂, u₁₆]. The communications device obtains a third information bit from S₅. For example, the third information bit is u₆, and the communications device changes u₆ in P₆ to a frozen bit, to obtain the binary vector P₄, where P₄=[0000001001110011]. After filling all the bits of the fourth code with values, the communications device obtains u¹⁶. Then, the communications device encodes u¹⁶, to obtain c¹⁶, where c¹⁶=u¹⁶F₁₆.

303: The communications device outputs the encoded bit sequence.

In this embodiment, the communications device encodes the to-be-encoded information bit sequence based on the binary vector P₁ of the first code, and outputs the encoded bit sequence after obtaining the encoded bit sequence. After outputting the encoded bit sequence, the communications device may send the encoded bit sequence.

According to the method described in FIG. 3, after receiving the to-be-encoded information bit sequence, the communications device may encode the to-be-encoded information bit sequence based on the binary vector P₁ of the first code, to obtain the encoded bit sequence, and output the encoded bit sequence. It can be understood that the method described in FIG. 3 provides a new encoding manner; and when encoding is performed in this encoding manner, parallel decoding can be performed in a decoding process. This helps reduce a decoding delay.

FIG. 8 is a schematic flowchart of another encoding method according to an embodiment. As shown in FIG. 8, the encoding method includes the following steps 801 to 805. For step 801, refer to the descriptions in step 301. Details are not described again herein. Step 802 to step 804 are a specific implementation in which a communications device encodes a to-be-encoded information bit sequence based on a binary vector P₁ of a first code to obtain an encoded bit sequence. Step 805 is a specific implementation of step 303.

801: A communications device obtains a to-be-encoded information bit sequence.

802: The communications device determines a binary vector P₇ of a seventh code based on a binary vector P₁ of a first code.

For descriptions of the binary vector P₁ of the first code and a manner of determining the binary vector P₁ of the first code, refer to the corresponding descriptions in the embodiment corresponding to FIG. 3. Details are not described herein again.

The binary vector P₇ indicates an information bit, a frozen bit, and a non-transmitted bit of the seventh code. A code length of the seventh code is n₇, a quantity of information bits of the seventh code is k₇, a quantity of non-transmitted bits of the seventh code is n₁−n₇, k₇ is equal to a length of the to-be-encoded information bit sequence, n₇ is an integer greater than k₇,

${n_{1} = 4^{\lceil\frac{\log_{2}{(n_{7})}}{2}\rceil}},$

and k₁ is greater than or equal to k₇. Optionally, k₁=k₇+n₁−n₇.

For example, the seventh code is a (13, 6) code, and the first code may be a (16, 9) code or a (16, 6) code. The seventh code is a (50, 2) code, and the first code may be a (64, 16) code or a (64, 2) code.

In the binary vector P₇, a non-transmitted bit may be indicated by using a preset value. For example, the preset value is 2. When p_(7,z)=1, it indicates that a z^(th) bit in to-be-encoded bits of the seventh code is an information bit. When p_(7,z)=0, it indicates that a z^(th) bit in to-be-encoded bits of the seventh code is a frozen bit. When p_(7,z)=2, it indicates that a z^(th) bit in encoded bits of the seventh code is a non-transmitted bit. Alternatively, the preset value may be another value such as 3, 4, or 5.

The following describes a specific implementation in which the communications device determines the binary vector P₇ of the seventh code based on the binary vector P₁ of the first code when k₁=k₇+n₁−n₇.

The communications device sequentially changes, according to a first preset rule, elements indicating information bits in P₁ to elements indicating non-transmitted bits, until a quantity of the elements indicating the non-transmitted bits in P₁ is equal to n₁−n₇, to obtain the binary vector P₇, where a value of the non-transmitted bit is independent of a value of the information bit of the seventh code. Based on this implementation, P₇ is determined, so that content corresponding to the information bit is not missed in a second bit sequence obtained after encoding. This helps ensure information integrity. Optionally, in this implementation, the non-transmitted bit may also be referred to as a shortened bit.

Optionally, the communications device sequentially changes, according to the first preset rule and based on a first binary sequence and a second binary sequence, the elements indicating the information bits in P₁ to the elements indicating the non-transmitted bits, until the quantity of the elements indicating the non-transmitted bits in P₁ is equal to n₁−n₇, to obtain the binary vector P₇. The first binary sequence includes binary sequence numbers that are of elements in P₁ and that are arranged in descending order or in ascending order. The second binary sequence also includes binary sequence numbers of elements in P₁. The first binary sequence and the second binary sequence are permuted.

For example, after receiving the to-be-encoded information bit sequence, the communications device may first determine the quantity of information bits of the seventh code, where the quantity of information bits of the seventh code is equal to the length of the to-be-encoded information bit sequence. After determining the quantity of information bits of the seventh code, the communications device determines the code length n₁ and the quantity k₁ of information bits of the first code based on the code length and the quantity of information bits of the seventh code. The code length of the seventh code may be preset. For example, the code length n₇ of the seventh code is 13, and the quantity k₇ of information bits of the seventh code is equal to 6.

${n_{1} = 4^{\lceil\frac{\log_{2}{(n_{7})}}{2}\rceil}},$

and k₁=k₇+n₁−n₇. Therefore, the communications device determines that the code length n₁ of the first code is 16 and the quantity k₁ of information bits of the first code is 9. Then, the communications device determines a code length and a quantity of information bits of a second code and a code length and a quantity of information bits of a third code based on the code length n₁ and the quantity k₁ of information bits of the first code. After determining the code length and the quantity of information bits of the second code and the code length and the quantity of information bits of the third code, the communications device determines P₂ of the second code and P₃ of the third code, and then determines P₁ based on P₂ and P₃.

For example, P₂=P₃=[0111], and P₁=P₂ ⊗P₃=[0000011101110111]. As shown in FIG. 9, the left box in FIG. 9 represents a first binary sequence. The first binary sequence includes binary sequence numbers of elements in P₁, and the binary sequence numbers in the left box are arranged in ascending order from top to bottom. 0000 indicates a sequence number 0 of the 1^(st) element in P₁, 0001 indicates a sequence number 1 of the 2^(nd) element in P₁, . . . , and 1111 indicates a sequence number 15 of the 16^(th) element in P₁. The right box in FIG. 9 represents a second binary sequence. In FIG. 9, binary sequence numbers in the right box and the binary sequence numbers in the left box are permuted.

As shown in FIG. 9, the communications device may determine, from the first binary sequence and the second binary sequence in a bottom-to-top order, the elements used to indicate the non-transmitted bits, until the quantity of the elements used to indicate the non-transmitted bits in P₁ is equal to 3. For example, an element value 2 is used to indicate a non-transmitted bit. The communications device determines, from the first binary sequence for the first time, that an element corresponding to 1111 is used to indicate a non-transmitted bit. Therefore, the communications device changes a value of the 16^(th) element in P₁ to 2. The communications device determines, from the second binary sequence for the second time, that an element corresponding to 1011 is used to indicate a non-transmitted bit. Therefore, the communications device changes a value of the 12^(th) element in P₁ to 2. The communications device determines, from the first binary sequence for the third time, that an element corresponding to 1110 is used to indicate a non-transmitted bit. Therefore, the communications device changes a value of the 15^(th) element in P₁ to 2. Finally, P₇=[0000011101120122].

A value of the non-transmitted bit is independent of a value of the information bit of the seventh code. Descriptions are provided with reference to a corresponding trellis graph. A first outer code in a trellis graph shown in FIG. 10 is a second inner code in a trellis graph shown in FIG. 11, and a first inner code in the trellis graph shown in FIG. 10 is a second outer code in the trellis graph shown in FIG. 11. The communications device may perform encoding by using an encoding process indicated by the trellis graph shown in FIG. 10 or FIG. 11. As shown in FIG. 10 and FIG. 11, u₆, u₇, u₈, u₁₀, u₁₁, and u₁₄ are information bits, u₁, u₂, u₃, u₄, u₅, u₉, and u₁₃ are frozen bits, c₁₂, c₁₅, and c₁₆ are non-transmitted bits, and u₁₂, u₁₅, and u₁₆ are to-be-encoded bits corresponding to the non-transmitted bits. It can be understood from FIG. 10 and FIG. 11 that a value of the non-transmitted bit c₁₆ is determined based on a value of u₁₆, a value of the non-transmitted bit c₁₂ is determined based on values of u₁₂ and u₁₆, a value of the non-transmitted bit c₁₅ is determined based on values of u₁₅ and u₁₆, and the non-transmitted bits c₁₂, c₁₅, and c₁₆ have no relationship with values of the information bits. Therefore, even if c₁₂, c₁₅, and c₁₆ are removed, content corresponding to the information bits is not missed in the second bit sequence. This helps ensure information integrity.

Further, if the first binary sequence includes binary sequence numbers that are of elements in P₁ and that are arranged in descending order, the communications device may determine, from the first binary sequence and the second binary sequence in a top-to-bottom order, the elements used to indicate the non-transmitted bits. A specific implementation principle is the same as a principle for the communications device to determine, from the first binary sequence and the second binary sequence in the bottom-to-top order, the elements used to indicate the non-transmitted bits. Details are not described herein again.

The following describes a specific implementation in which the communications device determines the binary vector P₇ of the seventh code based on the binary vector P₁ of the first code when k₁=k₇.

The communications device sequentially changes, according to a second preset rule, elements indicating frozen bits in P₁ to elements indicating non-transmitted bits, until a quantity of the elements indicating the non-transmitted bits in P₁ is equal to n₁−n₇, to obtain the binary vector P7. Based on this implementation, the non-transmitted bit can be properly determined. Optionally, in this implementation, the non-transmitted bit may also be referred to as a punctured bit.

Optionally, the communications device sequentially changes, according to the second preset rule and based on a first binary sequence and a second binary sequence, the elements indicating the frozen bits in P₁ to the elements indicating the non-transmitted bits, until the quantity of the elements indicating the non-transmitted bits in P₁ is equal to n₁−n₇, to obtain the binary vector P₇. The first binary sequence includes binary sequence numbers that are of elements in P₁ and that are arranged in descending order or in ascending order. The second binary sequence also includes binary sequence numbers of elements in P₁. The first binary sequence and the second binary sequence are permuted.

For example, the code length n₇ of the seventh code is 13, and the quantity k₇ of information bits of the seventh code is equal to 6. The communications device determines P₁=P₂⊗P₃=[0000001001110011] according to a principle the same as that in the foregoing example. The communications device determines the first binary sequence and the second binary sequence. For descriptions of the first binary sequence and the second binary sequence, refer to the foregoing descriptions.

As shown in FIG. 9, the communications device may determine, from the first binary sequence and the second binary sequence in a top-to-bottom order, the elements used to indicate the non-transmitted bits, until the quantity of the elements used to indicate the non-transmitted bits in P₁ is 3. For example, an element value 2 is used to indicate a non-transmitted bit. The communications device determines, from the first binary sequence for the first time, that an element corresponding to 0000 is used to indicate a non-transmitted bit. Therefore, the communications device changes a value of the 1^(st) element in P₁ to 2. The communications device determines, from the second binary sequence for the second time, that an element corresponding to 0100 is used to indicate a non-transmitted bit. Therefore, the communications device changes a value of the 5^(th) element in P₁ to 2. The communications device determines, from the first binary sequence for the third time, that an element corresponding to 0001 is used to indicate a non-transmitted bit. Therefore, the communications device changes a value of the 2^(nd) element in P₁ to 2. Finally, P₇=[2200201001110011].

Further, if the first binary sequence includes binary sequence numbers that are of elements in P₁ and that are arranged in descending order, the communications device may determine, from the first binary sequence and the second binary sequence in a top-to-bottom order, the elements used to indicate the non-transmitted bits. A specific implementation principle is the same as a principle for the communications device to determine, from the first binary sequence and the second binary sequence in the bottom-to-top order, the elements used to indicate the non-transmitted bits. Details are not described herein again.

803: The communications device encodes the to-be-encoded information bit sequence based on the binary vector P₇ of the seventh code, to obtain an encoded first bit sequence with a length of m.

804: The communications device removes a non-transmitted bit from the first bit sequence, to obtain a second bit sequence with a length of n₇.

805: The communications device outputs the second bit sequence.

In an optional implementation, a value of a to-be-encoded bit corresponding to the non-transmitted bit is a value pre-agreed upon by a transmitter end and a receiver end.

For example, the binary vector of the seventh code is P₇=[0000011101120122]. As shown in FIG. 10 or FIG. 11, u₆, u₇, u₈, u₁₀, u₁₁, and u₁₄ are information bits, u₁, u₂, u₃, u₄, u₅, u₉, and u₁₃ are frozen bits, and u₁₂, u₁₅, and u₁₆ are to-be-encoded bits corresponding to non-transmitted bits. The communications device fills u₆, u₇, u₈, u₁₀, u₁₁, and u₁₄ with information in the received to-be-encoded information bit sequence and fills the frozen bits and the non-transmitted bits u₁, u₂, u₃, u₄, u₅, u₉, u₁₂, u₁₃, u₁₅, and u₁₆ with fixed values, for example, 0, pre-agreed upon by the transmitter end and the receiver end. The communications device fills u₁₂, u₁₅, and u₁₆ with values pre-agreed upon by the transmitter end and the receiver end. A value filled in the non-transmitted bit by the communications device may be the same as or different from the fixed value filled in the frozen bit. After encoding u₁ to u₁₆, the communications device obtains the first bit sequences c₁ to c₁₆. The communications device removes the non-transmitted bits c₁₆, c₁₅, and c₁₂. Remaining bits c₁ to c₁₁, c₁₃, and c₁₄ form the second bit sequence. The communications device outputs the second bit sequence.

Based on the method described in FIG. 8, the communications device can construct a code with any code length.

An embodiment further provides another encoding method. The following further describes the another encoding method.

After a communications device receives a to-be-encoded information bit sequence, the communications device encodes the to-be-encoded information bit sequence based on a binary vector P₁ of a first code, to obtain an encoded bit sequence. After obtaining the encoded bit sequence, the communications device outputs the encoded bit sequence. P₁ indicates an information bit and a frozen bit of the first code, and P₁ is determined based on a target sequence and a quantity k₁ of information bits of the first code. The quantity k₁ of information bits of the first code is equal to a length of the to-be-encoded information bit sequence. A code length of the first code is n₁. The target sequence is a sequence that is extracted from a stored sequence with a length of M and that includes a sequence number less than or equal to n₁. The sequence with the length of M includes a sequence number corresponding to each of M bits, and M is greater than or equal to n₁.

For example, M is 16. The communications device may store a sequence with a length of 16. The sequence is [10, 14, 12, 16, 13, 7, 6, 9, 11, 5, 2, 4, 15, 8, 3, 1]. The sequence indicates the following: A sequence number corresponding to a bit m is 10; a sequence number corresponding to a bit u₂ is 14; a sequence number corresponding to a bit u₃ is 12; a sequence number corresponding to a bit u₄ is 16; a sequence number corresponding to a bit u₅ is 13; a sequence number corresponding to a bit u₆ is 7; a sequence number corresponding to a bit u₇ is 6; a sequence number corresponding to a bit u₈ is 9; a sequence number corresponding to a bit u₉ is 11; a sequence number corresponding to a bit u₁₀ is 5; a sequence number corresponding to a bit u₁₁ is 2; a sequence number corresponding to a bit u₁₂ is 4; a sequence number corresponding to a bit u₁₃ is 15; a sequence number corresponding to a bit u₁₄ is 8; a sequence number corresponding to a bit u₁₅ is 3; and a sequence number corresponding to a bit u₁₆ is 1.

It is assumed that the length of the to-be-encoded information bit sequence received by the communications device is 15. After receiving the to-be-encoded information bit sequence, the communications device may determine that the quantity of information bits of the first code is 15. The code length of the first code may be preset, for example, may be 16. For example, the first code is a (16, 15) code. After determining the first code, the communications device obtains the target sequence from the stored sequence with the length of 16 based on the code length of the first code. The target sequence is the sequence that is extracted from the stored sequence with the length of M and that includes the sequence number less than or equal to m. Both M and m are equal to 16. Therefore, the target sequence is [10, 14, 12, 16, 13, 7, 6, 9, 11, 5, 2, 4, 15, 8, 3, 1]. The communications device determines a bit with a sequence number less than or equal to 15 in the target sequence as an information bit and determines a bit with a sequence number greater than 15 in the target sequence as a frozen bit. Therefore, the communications device determines that P₁=[1110111111111111].

For another example, it is assumed that the length of the to-be-encoded information bit sequence received by the communications device is 9. After receiving the to-be-encoded information bit sequence, the communications device may determine that the quantity of information bits of the first code is 9. The code length of the first code may be preset, for example, may be 16. For example, the first code is a (16, 9) code. After determining the first code, the communications device obtains the target sequence from the stored sequence with the length of 16 based on the code length of the first code. The target sequence is the sequence that is extracted from the stored sequence with the length of M and that includes the sequence number less than or equal to m. Both M and m are equal to 16. Therefore, the target sequence is [10, 14, 12, 16, 13, 7, 6, 9, 11, 5, 2, 4, 15, 8, 3, 1]. The communications device determines a bit with a sequence number less than or equal to 9 in the target sequence as an information bit and determines a bit with a sequence number greater than 9 in the target sequence as a frozen bit. Therefore, the communications device determines that P₁=[0000011101110111].

In an optional implementation, the communications device may further generate the sequence with the length of M in advance. That the communications device generates the sequence with the length of M is implemented in the following manner: determining a set S₁ from an information bit indicated by a binary vector P₂ of a second code, where when an information bit included in the set S₁ is changed to a frozen bit, at least one information bit of a first inner code can be changed to a frozen bit in a first encoding process; determining a first information bit from the set S₁; changing the first information bit in P₂ to a frozen bit, to obtain a binary vector P₃ of a third code, where a code length of the second code is M, a quantity of information bits of the second code is K, a code length of the third code is M, and a quantity of information bits of the third code is K−1; determining that a sequence number corresponding to the first information bit is K; and traversing K from M to 1, to determine a sequence number corresponding to each bit in the sequence with the length of M.

Optionally, the set S₁ includes a plurality of information bits; and compared with another information bit in the set S₁, when the first information bit in the set S₁ is changed to a frozen bit, an information bit that is of the first inner code and that is changed to a frozen bit has a lowest reliability rank. Alternatively, the first information bit may be any information bit in the set S₁.

Herein, the second code and the third code are different from the second code and the third code in the embodiment described in FIG. 3. Herein, the code length of the second code is M, the quantity of information bits of the second code is K, the code length of the third code is M, and the quantity of information bits of the third code is K−1.

For example, a sequence with a length of 16 needs to be generated. First, K=16 is set. The communications device determines P₃ of the (16,15) third code based on the binary vector P₂=[1111111111111111] of the (16,16) second code. Herein, the communications device may determine, according to a principle the same as the principle for determining the set S₃ in the foregoing method embodiment, the set S₁ from the information bit indicated by P₂ of the second code. Then, the first information bit is obtained from the set S₁. The communications device changes the first information bit in P₂ to the frozen bit, to obtain P₃ of the third code. For example, if the first information bit is u₄, P₃=[1110111111111111]. The communications device determines that a sequence number corresponding to u₄ in the sequence with the length of 16 is 16.

Then, K=15 is set. The communications device determines P₃ of the (16, 14) third code of based on the binary vector P₂=[1110111111111111] of the (16, 15) second code. For example, if the first information bit is u₁₃, P₃=[1110111111110111]. The communications device determines that a sequence number corresponding to u₁₃ in the sequence with the length of 16 is 15. Similar operations are performed, until sequence numbers corresponding to all bits are determined. Then, the sequence numbers corresponding to all the bits form the sequence with the length of 16, and the sequence is stored in the communications device. For example, the sequence [10, 14, 12, 16, 13, 7, 6, 9, 11, 5, 2, 4, 15, 8, 3, 1] with the length of 16 is finally obtained.

In this embodiment, a sequence with a length of 4096 that is obtained in the foregoing manner when M is 4096 is further provided. Sequence numbers included in the sequence may be shown in Table 1, and the sequence may be prestored.

TABLE 1 Sequence with the length of M = 4096 Index Sequence number 1 3970 2 3972 3 3974 4 3976 5 3978 6 3980 7 3982 8 3984 9 3986 10 3988 11 3990 12 3992 13 3994 14 3996 15 3998 16 4000 17 4002 18 4004 19 4006 20 4008 21 4010 22 4012 23 4014 24 4016 25 4018 26 4020 27 4022 28 4024 29 4026 30 4028 31 4030 32 4032 33 4034 34 4036 35 4038 36 4040 37 4042 38 4044 39 4046 40 4048 41 4050 42 4052 43 4054 44 4056 45 4058 46 4060 47 4062 48 4064 49 4066 50 4068 51 4070 52 4072 53 4074 54 4076 55 4078 56 4080 57 4082 58 4084 59 4086 60 4088 61 4090 62 4092 63 4094 64 4096 65 3971 66 3845 67 3847 68 3849 69 3851 70 3853 71 3855 72 3857 73 3859 74 3861 75 3863 76 3865 77 3867 78 3869 79 3871 80 3873 81 3875 82 3877 83 3879 84 3881 85 3883 86 3885 87 3887 88 3889 89 3891 90 3893 91 3895 92 3897 93 3899 94 3901 95 3903 96 3905 97 3907 98 3909 99 3911 100 3913 101 3915 102 3919 104 3921 105 3923 106 3925 107 3927 108 3929 109 3931 110 3933 111 3935 112 3937 113 3939 114 3941 115 3943 116 3945 117 3947 118 3949 119 3951 120 3953 121 3955 122 3957 123 3959 124 3961 125 3963 126 3965 127 3967 128 3969 129 3973 130 3846 131 3722 132 3724 133 3726 134 3728 135 3730 136 3732 137 3734 138 3736 139 3738 140 3740 141 3742 142 3744 143 3746 144 3748 145 3750 146 3752 147 3754 148 3756 149 3758 150 3760 151 3762 152 3764 153 3766 154 3768 155 3770 156 3772 157 3774 158 3776 159 3778 160 3780 161 3782 162 3784 163 3786 164 3788 165 3790 166 3792 167 3794 168 3796 169 3798 170 3800 171 3802 172 3804 173 3806 174 3808 175 3810 176 3812 177 3814 178 3816 179 3818 180 3820 181 3822 182 3824 183 3826 184 3828 185 3830 186 3832 187 3834 188 3836 189 3838 190 3840 191 3842 192 3844 193 3975 194 3848 195 3723 196 3250 197 3601 198 3252 199 3254 200 3256 201 3482 202 3258 203 3260 204 3262 205 3264 206 3266 207 3268 208 3270 209 3365 210 3272 211 3274 212 3276 213 3278 214 3280 215 3282 216 3284 217 3286 218 3288 219 3290 220 3292 221 3294 222 3296 223 3298 224 3300 225 3302 226 3304 227 3306 228 3308 229 3310 230 3312 231 3314 232 3316 233 3318 234 3320 235 3322 236 3324 237 3326 238 3328 239 3330 240 3332 241 3334 242 3336 243 3338 244 3340 245 3342 246 3344 247 3346 248 3348 249 3350 250 3352 251 3354 252 3356 253 3358 254 3360 255 3362 256 3364 257 3977 258 3850 259 3725 260 3602 261 3603 262 3605 263 3607 264 3609 265 3611 266 3613 267 3615 268 3617 269 3619 270 3621 271 3623 272 3625 273 3627 274 3629 275 3631 276 3633 277 3635 278 3637 279 3639 280 3641 281 3643 282 3645 283 3647 284 3649 285 3651 286 3653 287 3655 288 3657 289 3659 290 3661 291 3663 292 3665 293 3667 294 3669 295 3671 296 3673 297 3675 298 3677 299 3679 300 3681 301 3683 302 3685 303 3687 304 3689 305 3691 306 3693 307 3695 308 3697 309 3699 310 3701 311 3703 312 3705 313 3707 314 3709 315 3711 316 3713 317 3715 318 3717 319 3719 320 3721 321 3979 322 3852 323 3727 324 3251 325 3604 326 3026 327 3028 328 3030 329 3484 330 3032 331 3034 332 3036 333 3038 334 3040 335 3042 336 3044 337 3367 338 3046 339 3048 340 3050 341 3052 342 3054 343 3056 344 3058 345 3060 346 3062 347 3064 348 3066 349 3068 350 3070 351 3072 352 3074 353 3137 354 3076 355 3078 356 3080 357 3082 358 3084 359 3086 360 3088 361 3090 362 3092 363 3094 364 3096 365 3098 366 3100 367 3102 368 3104 369 3106 370 3108 371 3110 372 3112 373 3114 374 3116 375 3118 376 3120 377 3122 378 3124 379 3126 380 3128 381 3130 382 3132 383 3134 384 3136 385 3981 386 3854 387 3729 388 3253 389 3606 390 3027 391 2917 392 2919 393 3486 394 2921 395 2923 396 2925 397 2927 398 2929 399 2931 400 2933 401 3369 402 2935 403 2937 404 2939 405 2941 406 2943 407 2945 408 2947 409 2949 410 2951 411 2953 412 2955 413 2957 414 2959 415 2961 416 2963 417 3139 418 2965 419 2967 420 2969 421 2971 422 2973 423 2975 424 2977 425 2979 426 2981 427 2983 428 2985 429 2987 430 2989 431 2991 432 2993 433 2995 434 2997 435 2999 436 3001 437 3003 438 3005 439 3007 440 3009 441 3011 442 3013 443 3015 444 3017 445 3019 446 3021 447 3023 448 3025 449 3983 450 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1476 2640 843 2641 3436 2642 2659 2643 2455 2644 1555 2645 2259 2646 1326 2647 1182 2648 845 2649 1980 2650 1113 2651 981 2652 847 2653 849 2654 851 2655 853 2656 855 2657 3204 2658 2356 2659 2164 2660 1253 2661 1891 2663 918 2664 857 2665 1719 2666 858 2667 860 2668 862 2669 864 2670 866 2671 868 2672 870 2673 1400 2674 872 2675 874 2676 876 2677 878 2678 880 2679 882 2680 884 2681 886 2682 888 2683 890 2684 892 2685 894 2686 896 2687 898 2688 900 2689 4053 2690 3926 2691 3801 2692 3321 2693 3678 2694 3093 2695 2982 2696 2073 2697 3557 2698 2873 2699 2766 2700 1806 2701 2558 2702 1638 2703 1478 2704 731 2705 3438 2706 2661 2707 2457 2708 1557 2709 2261 2710 1328 2711 1184 2712 733 2713 1982 2714 1115 2715 983 2716 735 2717 800 2718 737 2719 739 2720 741 2721 3206 2722 2358 2723 2166 2724 1255 2725 1893 2726 1048 2727 920 2728 743 2729 1721 2730 859 2731 744 2732 746 2733 748 2734 750 2735 752 2736 754 2737 1402 2738 756 2739 758 2740 760 2741 762 2742 764 2743 766 2744 768 2745 770 2746 772 2747 774 2748 776 2749 778 2750 780 2751 782 2752 784 2753 4055 2754 3928 2755 3803 2756 3323 2757 3680 2758 3095 2759 2984 2760 2075 2761 3559 2762 2875 2763 2768 2764 1808 2765 2560 2766 1640 2767 1480 2768 690 2769 3440 2770 2663 2771 2459 2772 1559 2773 2263 2774 1330 2775 1186 2776 496 2777 1984 2778 1117 2779 985 2780 410 2781 802 2782 295 2783 258 2784 260 2785 3208 2786 2360 2787 2168 2788 1257 2789 1895 2790 1050 2791 922 2792 369 2793 1723 2794 861 2795 745 2796 261 2797 589 2798 263 2799 265 2800 267 2801 1404 2802 638 2803 542 2804 269 2805 452 2806 271 2807 273 2808 275 2809 331 2810 277 2811 279 2812 281 2813 283 2814 285 2815 287 2816 289 2817 4057 2818 3930 2819 3805 2820 3325 2821 3682 2822 3097 2823 2986 2824 2077 2825 3561 2826 2877 2827 2770 2828 1810 2829 2562 2830 1642 2831 1482 2832 692 2833 3442 2834 2665 2835 2461 2836 1561 2837 2265 2838 1332 2839 1188 2840 578 2841 1986 2842 1119 2843 987 2844 580 2845 804 2846 582 2847 584 2848 586 2849 3210 2850 2362 2851 2170 2852 1259 2853 1897 2854 1052 2855 924 2856 588 2857 1725 2858 863 2859 747 2860 590 2861 591 2862 593 2863 595 2864 597 2865 1406 2866 640 2867 599 2868 601 2869 603 2870 605 2871 607 2872 609 2873 611 2874 613 2875 615 2876 617 2877 619 2878 621 2879 623 2880 625 2881 4059 2882 3932 2883 3807 2884 3327 2885 3684 2886 3099 2887 2988 2888 2079 2889 3563 2890 2879 2891 2772 2892 1812 2893 2564 2894 1644 2895 1484 2896 694 2897 3444 2898 2667 2899 2463 2900 1563 2901 2267 2902 1334 2903 1190 2904 498 2905 1988 2906 1121 2907 989 2908 412 2909 806 2910 297 2911 229 2912 198 2913 3212 2914 2364 2915 2172 2916 1261 2917 1899 2918 1054 2919 926 2920 371 2921 1727 2922 865 2923 749 2924 262 2925 592 2926 199 2927 201 2928 203 2929 1408 2930 642 2931 544 2932 205 2933 454 2934 207 2935 209 2936 211 2937 333 2938 213 2939 215 2940 217 2941 219 2942 221 2943 223 2944 225 2945 4061 2946 3934 2947 3809 2948 3329 2949 3686 2950 3101 2951 2990 2952 2081 2953 3565 2954 2881 2955 2774 2956 1814 2957 2566 2958 1646 2959 1486 2960 696 2961 3446 2962 2669 2963 2465 2964 1565 2965 2269 2966 1336 2967 1192 2968 500 2969 1990 2970 1123 2971 991 2972 414 2973 808 2974 299 2975 231 2976 146 2977 3214 2978 2366 2979 2174 2980 1263 2981 1901 2982 1056 2983 928 2984 373 2985 1729 2986 867 2987 751 2988 264 2989 594 2990 200 2991 147 2992 149 2993 1410 2994 644 2995 546 2996 172 2997 456 2998 151 2999 153 3000 155 3001 335 3002 157 3003 159 3004 161 3005 163 3006 165 3007 167 3008 169 3009 4063 3010 3936 3011 3811 3012 3331 3013 3688 3014 3103 3015 2992 3016 2083 3017 3567 3018 2883 3019 2776 3020 1816 3021 2568 3022 1648 3023 1488 3024 698 3025 3448 3026 2671 3027 2467 3028 1567 3029 2271 3030 1338 3031 1194 3032 502 3033 1992 3034 1125 3035 993 3036 416 3037 810 3038 301 3039 233 3040 51 3041 3216 3042 2368 3043 2176 3044 1265 3045 1903 3046 1058 3047 930 3048 375 3049 1731 3050 869 3051 753 3052 266 3053 596 3054 202 3055 148 3056 26 3057 1412 3058 646 3059 548 3060 174 3061 458 3062 124 3063 103 3064 28 3065 337 3066 84 3067 67 3068 30 3069 37 3070 32 3071 34 3072 36 3073 4065 3074 3938 3075 3813 3076 3333 3077 3690 3078 3105 3079 2994 3080 2085 3081 3569 3082 2885 3083 2778 3084 1818 3085 2570 3086 1650 3087 1490 3088 1371 3089 3450 3090 2673 3091 2469 3092 1569 3093 2273 3094 1373 3095 1375 3096 1377 3097 1994 3098 1379 3099 1381 3100 1383 3101 1385 3102 1387 3103 1389 3104 1391 3105 3218 3106 2370 3107 2178 3108 1393 3109 1905 3110 1395 3111 1397 3112 1399 3113 1733 3114 1401 3115 1403 3116 1405 3117 1407 3118 1409 3119 1411 3120 1413 3121 1414 3122 1416 3123 1418 3124 1420 3125 1422 3126 1424 3127 1426 3128 1428 3129 1430 3130 1432 3131 1434 3132 1436 3133 1438 3134 1440 3135 1442 3136 1444 3137 4067 3138 3940 3139 3815 3140 3335 3141 3692 3142 3107 3143 2996 3144 2087 3145 3571 3146 2887 3147 2780 3148 1820 3149 2572 3150 1652 3151 1492 3152 700 3153 3452 3154 2675 3155 2471 3156 1571 3157 2275 3158 1340 3159 1196 3160 627 3161 1996 3162 1127 3163 995 3164 629 3165 812 3166 631 3167 633 3168 635 3169 3220 3170 2372 3171 2180 3172 1267 3173 1907 3175 932 3176 637 3177 1735 3178 871 3179 755 3180 639 3181 641 3182 643 3183 645 3184 647 3185 1415 3186 648 3187 650 3188 652 3189 654 3190 656 3191 658 3192 660 3193 662 3194 664 3195 666 3196 668 3197 670 3198 672 3199 674 3200 676 3201 4069 3202 3942 3203 3817 3204 3337 3205 3694 3206 3109 3207 2998 3208 2089 3209 3573 3210 2889 3211 2782 3212 1822 3213 2574 3214 1654 3215 1494 3216 702 3217 3454 3218 2677 3219 2473 3220 1573 3221 2277 3222 1342 3223 1198 3224 531 3225 1998 3226 1129 3227 997 3228 533 3229 814 3230 535 3231 537 3232 539 3233 3222 3234 2374 3235 2182 3236 1269 3237 1909 3238 1062 3239 934 3240 541 3241 1737 3242 873 3243 757 3244 543 3245 598 3246 545 3247 547 3248 549 3249 1417 3250 649 3251 550 3252 552 3253 554 3254 556 3255 558 3256 560 3257 562 3258 564 3259 566 3260 568 3261 570 3262 572 3263 574 3264 576 3265 4071 3266 3944 3267 3819 3268 3339 3269 3696 3270 3111 3271 3000 3272 2091 3273 3575 3274 2891 3275 2784 3276 1824 3277 2576 3278 1656 3279 1496 3280 704 3281 3456 3282 2679 3283 2475 3284 1575 3285 2279 3286 1344 3287 1200 3288 504 3289 2000 3290 1131 3291 999 3292 418 3293 816 3294 303 3295 235 3296 171 3297 3224 3298 2376 3299 2184 3300 1271 3301 1911 3302 1064 3303 936 3304 377 3305 1739 3306 875 3307 759 3308 268 3309 600 3310 204 3311 173 3312 175 3313 1419 3314 651 3315 551 3316 176 3317 460 3318 178 3319 180 3320 182 3321 339 3322 184 3323 186 3324 188 3325 190 3326 192 3327 194 3328 196 3329 4073 3330 3946 3331 3821 3332 3341 3333 3698 3334 3113 3335 3002 3336 2093 3337 3577 3338 2893 3339 2786 3340 1826 3341 2578 3342 1658 3343 1498 3344 706 3345 3458 3346 2681 3347 2477 3348 1577 3349 2281 3350 1346 3351 1202 3352 506 3353 2002 3354 1133 3355 1001 3356 443 3357 818 3358 445 3359 447 3360 449 3361 3226 3362 2378 3363 2186 3364 1273 3365 1913 3366 1066 3367 938 3368 451 3369 1741 3370 877 3371 761 3372 453 3373 602 3374 455 3375 457 3376 459 3377 1421 3378 653 3379 553 3380 461 3381 462 3382 464 3383 466 3384 468 3385 470 3386 472 3387 474 3388 476 3389 478 3390 480 3391 482 3392 484 3393 4075 3394 3948 3395 3823 3396 3343 3397 3700 3398 3115 3399 3004 3400 2095 3401 3579 3402 2895 3403 2788 3404 1828 3405 2580 3406 1660 3407 1500 3408 708 3409 3460 3410 2683 3411 2479 3412 1579 3413 2283 3414 1348 3415 1204 3416 508 3417 2004 3418 1135 3419 1003 3420 420 3421 820 3422 305 3423 237 3424 123 3425 3228 3426 2380 3427 2188 3428 1275 3429 1915 3430 1068 3431 940 3432 379 3433 1743 3434 879 3435 763 3436 270 3437 604 3438 206 3439 150 3440 125 3441 1423 3442 655 3443 555 3444 177 3445 463 3446 126 3447 128 3448 130 3449 341 3450 132 3451 134 3452 136 3453 138 3454 140 3455 142 3456 144 3457 4077 3458 3950 3459 3825 3460 3345 3461 3702 3462 3117 3463 3006 3464 2097 3465 3581 3466 2897 3467 2790 3468 1830 3469 2582 3470 1662 3471 1502 3472 710 3473 3462 3474 2685 3475 2481 3476 1581 3477 2285 3478 1350 3479 1206 3480 510 3481 2006 3482 1137 3483 1005 3484 422 3485 822 3486 307 3487 239 3488 102 3489 3230 3490 2382 3491 2190 3492 1277 3493 1917 3494 1070 3495 942 3496 381 3497 1745 3498 881 3499 765 3500 272 3501 606 3502 208 3503 152 3504 104 3505 1425 3506 657 3507 557 3508 179 3509 465 3510 127 3511 105 3512 107 3513 343 3514 109 3515 111 3516 113 3517 115 3518 117 3519 119 3520 121 3521 4079 3522 3952 3523 3827 3524 3347 3525 3704 3526 3119 3527 3008 3528 2099 3529 3583 3530 2899 3531 2792 3532 1832 3533 2584 3534 1664 3535 1504 3536 712 3537 3464 3538 2687 3539 2483 3540 1583 3541 2287 3542 1352 3543 1208 3544 512 3545 2008 3546 1139 3547 1007 3548 424 3549 824 3550 309 3551 241 3552 53 3553 3232 3554 2384 3555 2192 3556 1279 3557 1919 3558 1072 3559 944 3560 383 3561 1747 3562 883 3563 767 3564 274 3565 608 3566 210 3567 154 3568 27 3569 1427 3570 659 3571 559 3572 181 3573 467 3574 129 3575 106 3576 17 3577 345 3578 86 3579 69 3580 19 3581 39 3582 21 3583 23 3584 25 3585 4081 3586 3954 3587 3829 3588 3349 3589 3706 3590 3121 3591 3010 3592 2101 3593 3585 3594 2901 3595 2794 3596 1834 3597 2586 3598 1666 3599 1506 3600 714 3601 3466 3602 2689 3603 2485 3604 1585 3605 2289 3606 1354 3607 1210 3608 514 3609 2010 3610 1141 3611 1009 3612 426 3613 826 3614 326 3615 328 3616 330 3617 3234 3618 2386 3619 2194 3620 1281 3621 1921 3622 1074 3623 946 3624 385 3625 1749 3626 885 3627 769 3628 332 3629 610 3630 334 3631 336 3632 338 3633 1429 3634 661 3635 561 3636 340 3637 469 3638 342 3639 344 3640 346 3641 347 3642 349 3643 351 3644 353 3645 355 3646 357 3617 359 3618 361 3619 4083 3650 3956 3651 3831 3652 3351 3653 3708 3654 3123 3655 3012 3656 2103 3657 3587 3658 2903 3659 2796 3660 1836 3661 2588 3662 1668 3663 1508 3664 716 3665 3468 3666 2691 3667 2487 3668 1587 3669 2291 3670 1356 3671 1212 3672 516 3673 2012 3674 1143 3675 1011 3676 428 3677 828 3678 311 3679 243 3680 83 3681 3236 3682 2388 3683 2196 3684 1283 3685 1923 3687 948 3688 387 3689 1751 3690 887 3691 771 3692 276 3693 612 3694 212 3695 156 3696 85 3697 1431 3698 663 3699 563 3700 183 3701 471 3702 131 3703 108 3704 87 3705 348 3706 88 3707 90 3708 92 3709 94 3710 96 3711 98 3712 100 3713 4085 3714 3958 3715 3833 3716 3353 3717 3710 3718 3125 3719 3014 3720 2105 3721 3589 3722 2905 3723 2798 3724 1838 3725 2590 3726 1670 3727 1510 3728 718 3729 3470 3730 2693 3731 2489 3732 1589 3733 2293 3734 1358 3735 1214 3736 518 3737 2014 3738 1145 3739 1013 3740 430 3741 830 3742 313 3743 245 3744 66 3745 3238 3746 2390 3747 2198 3748 1285 3749 1925 3750 1078 3751 950 3752 389 3753 1753 3754 889 3755 773 3756 278 3757 614 3758 214 3759 158 3760 68 3761 1433 3762 665 3763 565 3764 185 3765 473 3766 133 3767 110 3768 70 3769 350 3770 89 3771 71 3772 73 3773 75 3774 77 3775 79 3776 81 3777 4087 3778 3960 3779 3835 3780 3355 3781 3712 3782 3127 3783 3016 3784 2107 3785 3591 3786 2907 3787 2800 3788 1840 3789 2592 3790 1672 3791 1512 3792 720 3793 3472 3794 2695 3795 2491 3796 1591 3797 2295 3798 1360 3799 1216 3800 520 3801 2016 3802 1147 3803 1015 3804 432 3805 832 3806 315 3807 247 3808 55 3809 3240 3810 2392 3811 2200 3812 1287 3813 1927 3814 1080 3815 952 3816 391 3817 1755 3818 891 3819 775 3820 280 3821 616 3822 216 3823 160 3824 29 3825 1435 3826 667 3827 567 3828 187 3829 475 3830 135 3831 112 3832 18 3833 352 3834 91 3835 72 3836 10 3837 41 3838 12 3839 14 3840 16 3841 4089 3842 3962 3843 3837 3844 3357 3845 3714 3846 3129 3847 3018 3848 2109 3849 3593 3850 2909 3851 2802 3852 1842 3853 2594 3854 1674 3855 1514 3856 722 3857 3474 3858 2697 3859 2493 3860 1593 3861 2297 3862 1362 3863 1218 3864 522 3865 2018 3866 1149 3867 1017 3868 434 3869 834 3870 317 3871 249 3872 57 3873 3242 3874 2394 3875 2202 3876 1289 3877 1929 3878 1082 3879 954 3880 393 3881 1757 3882 893 3883 777 3884 282 3885 618 3886 218 3887 162 3888 38 3889 1437 3890 669 3891 569 3892 189 3893 477 3894 137 3895 114 3896 40 3897 354 3898 93 3899 74 3900 42 3901 43 3902 45 3903 47 3904 49 3905 4091 3906 3964 3907 3839 3908 3359 3909 3716 3910 3131 3911 3020 3912 2111 3913 3595 3914 2911 3915 2804 3916 1844 3917 2596 3918 1676 3919 1516 3920 724 3921 3476 3922 2699 3923 2495 3924 1595 3925 2299 3926 1364 3927 1220 3928 524 3929 2020 3930 1151 3931 1019 3932 436 3933 836 3934 319 3935 251 3936 59 3937 3244 3938 2396 3939 2204 3940 1291 3941 1931 3942 1084 3943 956 3944 395 3945 1759 3946 895 3947 779 3948 284 3949 620 3950 220 3951 164 3952 31 3953 1439 3954 671 3955 571 3956 191 3957 479 3958 139 3959 116 3960 20 3961 356 3962 95 3963 76 3964 11 3965 44 3966 5 3967 7 3968 9 3969 4093 3970 3966 3971 3841 3972 3361 3973 3718 3974 3133 3975 3022 3976 2113 3977 3597 3978 2913 3979 2806 3980 1846 3981 2598 3982 1678 3983 1518 3984 726 3985 3478 3986 2701 3987 2497 3988 1597 3989 2301 3990 1366 3991 1222 3992 526 3993 2022 3994 1153 3995 1021 3996 438 3997 838 3998 321 3999 253 4000 61 4001 3246 4002 2398 4003 2206 4004 1293 4005 1933 4006 1086 4007 958 4008 397 4009 1761 4010 897 4011 781 4012 286 4013 622 4014 222 4015 166 4016 33 4017 1441 4018 673 4019 573 4020 193 4021 481 4022 141 4023 118 4024 22 4025 358 4026 97 4027 78 4028 13 4029 46 4030 6 4031 2 4032 4 4033 4095 4034 3968 4035 3843 4036 3363 4037 3720 4038 3135 4039 3024 4040 2115 4041 3599 4042 2915 4043 2808 4044 1848 4045 2600 4046 1680 4047 1520 4048 728 4049 3480 4050 2703 4051 2499 4052 1599 4053 2303 4054 1368 4055 1224 4056 528 4057 2024 4058 1155 4059 1023 4060 440 4061 840 4062 323 4063 255 4064 63 4065 3248 4066 2400 4067 2208 4068 1295 4069 1935 4070 1088 4071 960 4072 399 4073 1763 4074 899 4075 783 4076 288 4077 624 4078 224 4079 168 4080 35 4081 1443 4082 675 4083 575 4084 195 4085 483 4086 143 4087 120 4088 24 4089 360 4090 99 4091 80 4092 15 4093 48 4094 8 4095 3 4096 1

A sequence with a length of an even power of 2 may be constructed by using the foregoing sequence construction method provided in this embodiment, or may be obtained from a longer sequence based on a nested feature (for example, a sequence with a length of 1024 may be obtained from the foregoing sequence with the length of 4096 by reading sequence numbers less than or equal to 1024 in order). The sequence with the length of the even power of 2 constructed by using the foregoing sequence construction method may be the same as or different from the sequence with the length of the even power of 2 obtained from the longer sequence based on the nested feature. For example, as shown in Table 2, an embodiment further provides a sequence with a length of M=1024 constructed by using the foregoing sequence construction method. The sequence may be prestored. It should be noted that the sequence corresponding to M=1024 may be constructed in a manner such as an NR sequence or a PW sequence.

TABLE 2 Sequence with the length of M = 1024 Se- Se- Se- Se- Se- Se- Sequence Sequence quence quence quence quence quence quence Index number Index number Index number Index number Index number Index number Index number Index number 1 962 129 969 257 977 385 985 513 993 641 1001 769 1009 897 1017 2 964 130 906 258 914 386 922 514 930 642 938 770 946 898 954 3 966 131 845 259 853 387 861 515 869 643 877 771 885 899 893 4 968 132 786 260 731 388 639 516 678 644 653 772 661 900 669 5 970 133 787 261 794 389 802 517 810 645 818 773 826 901 834 6 972 134 789 262 733 390 588 518 680 646 602 774 610 902 618 7 974 135 791 263 735 391 539 519 682 647 553 775 561 903 569 8 976 136 793 264 737 392 363 520 684 648 291 776 274 904 282 9 978 137 795 265 738 393 745 521 753 649 761 777 769 905 777 10 980 138 797 266 740 394 492 522 686 650 506 778 514 906 522 11 982 139 799 267 742 395 447 523 688 651 461 779 469 907 477 12 984 140 801 268 744 396 365 524 690 652 293 780 227 908 218 13 986 141 803 269 746 397 366 525 692 653 377 781 385 909 393 14 988 142 805 270 748 398 368 526 694 654 295 782 229 910 189 15 990 143 807 271 750 399 370 527 696 655 297 783 231 911 137 16 992 144 809 272 752 400 372 528 698 656 299 784 233 912 38 17 994 145 811 273 754 401 691 529 699 657 706 785 714 913 722 18 996 146 813 274 756 402 405 530 701 658 418 786 426 914 434 19 998 147 815 275 758 403 374 531 703 659 338 787 346 915 354 20 1000 148 817 276 760 404 376 532 705 660 301 788 235 916 162 21 1002 149 819 277 762 405 378 533 707 661 302 789 309 917 317 22 1004 150 821 278 764 406 380 534 709 662 304 790 237 918 114 23 1006 151 823 279 766 407 382 535 711 663 306 791 239 919 93 24 1008 152 825 280 768 408 384 536 713 664 308 792 241 920 40 25 1010 153 827 281 770 409 386 537 715 665 310 793 242 921 249 26 1012 154 829 282 772 410 388 538 717 666 312 794 244 922 74 27 1014 155 831 283 774 411 390 539 719 667 314 795 246 923 57 28 1016 156 833 284 776 412 392 540 721 668 316 796 248 924 42 29 1018 157 835 285 778 413 394 541 723 669 318 797 250 925 43 30 1020 158 837 286 780 414 396 542 725 670 320 798 252 926 45 31 1022 159 839 287 782 415 398 543 727 671 322 799 254 927 47 32 1024 160 841 288 784 416 400 544 729 672 324 800 256 928 49 33 963 161 971 289 979 417 987 545 995 673 1003 801 1011 929 1019 34 901 162 908 290 916 418 924 546 932 674 940 802 948 930 956 35 903 163 847 291 855 419 863 547 871 675 879 803 887 931 895 36 905 164 627 292 633 420 641 548 647 676 655 804 663 932 671 37 907 165 788 293 796 421 804 549 812 677 820 805 828 933 836 38 909 166 577 294 582 422 590 550 596 678 604 806 612 934 620 39 911 167 579 295 533 423 541 551 547 679 555 807 563 935 571 40 913 168 581 296 486 424 260 552 402 680 268 808 276 936 284 41 915 169 732 297 739 425 747 553 755 681 763 809 771 937 779 42 917 170 583 298 487 426 494 554 500 682 508 810 516 938 524 43 919 171 585 299 489 427 449 555 455 683 463 811 471 939 479 44 921 172 587 300 491 428 198 556 404 684 206 812 212 940 220 45 923 173 589 301 493 429 367 557 406 685 379 813 387 941 395 46 925 174 591 302 495 430 170 558 408 686 177 814 183 942 191 47 927 175 593 303 497 431 172 559 410 687 125 815 131 943 139 48 929 176 595 304 499 432 174 560 412 688 102 816 66 944 31 49 931 177 679 305 685 433 693 561 700 689 708 817 716 945 724 50 933 178 597 306 501 434 407 562 413 690 420 818 428 946 436 51 935 179 599 307 503 435 329 563 415 691 340 819 348 947 356 52 937 180 601 308 505 436 176 564 417 692 150 820 156 948 164 53 939 181 603 309 507 437 294 565 419 693 303 821 311 949 319 54 941 182 605 310 509 438 178 566 421 694 103 822 108 950 116 55 943 183 607 311 511 439 180 567 423 695 105 823 87 951 95 56 945 184 609 312 513 440 182 568 425 696 107 824 68 952 20 57 947 185 611 313 515 441 228 569 427 697 236 825 243 953 251 58 949 186 613 314 517 442 184 570 429 698 109 826 69 954 76 59 951 187 615 315 519 443 186 571 431 699 111 827 71 955 59 60 953 188 617 316 521 444 188 572 433 700 113 828 73 956 11 61 955 189 619 317 523 445 190 573 435 701 115 829 75 957 44 62 957 190 621 318 525 446 192 574 437 702 117 830 77 958 5 63 959 191 623 319 527 447 194 575 439 703 119 831 79 959 7 64 961 192 625 320 529 448 196 576 441 704 121 832 81 960 9 65 965 193 973 321 981 449 989 577 997 705 1005 833 1013 961 1021 66 902 194 910 322 918 450 926 578 934 706 942 834 950 962 958 67 842 195 849 323 857 451 865 579 873 707 881 835 889 963 897 68 844 196 629 324 635 452 643 580 649 708 657 836 665 964 673 69 846 197 790 325 798 453 806 581 814 709 822 837 830 965 838 70 848 198 578 326 584 454 592 582 598 710 606 838 614 966 622 71 850 199 530 327 535 455 543 583 549 711 557 839 565 967 573 72 852 200 532 328 443 456 262 584 326 712 270 840 278 968 286 73 854 201 734 329 741 457 749 585 757 713 765 841 773 969 781 74 856 202 534 330 488 458 496 586 502 714 510 842 518 970 526 75 858 203 536 331 444 459 451 587 457 715 465 843 473 971 481 76 860 204 538 332 446 460 200 588 328 716 208 844 214 972 222 77 862 205 540 333 448 461 369 589 373 717 381 845 389 973 397 78 864 206 542 334 450 462 171 590 330 718 179 846 185 974 193 79 866 207 544 335 452 463 122 591 332 719 127 847 133 975 141 80 868 208 546 336 454 464 124 592 334 720 83 848 51 976 33 81 870 209 681 337 687 465 695 593 702 721 710 849 718 977 726 82 872 210 548 338 456 466 409 594 414 722 422 850 430 978 438 83 874 211 550 339 458 467 331 595 335 723 342 851 350 979 358 84 876 212 552 340 460 468 145 596 337 724 152 852 158 980 166 85 878 213 554 341 462 469 296 597 339 725 305 853 313 981 321 86 880 214 556 342 464 470 126 598 341 726 104 854 110 982 118 87 882 215 558 343 466 471 128 599 343 727 84 855 89 983 97 88 884 216 560 344 468 472 130 600 345 728 86 856 53 984 22 89 886 217 562 345 470 473 230 601 347 729 238 857 245 985 253 90 888 218 564 346 472 474 132 602 349 730 88 858 70 986 78 91 890 219 566 347 474 475 134 603 351 731 90 859 54 987 61 92 892 220 568 348 476 476 136 604 353 732 92 860 56 988 13 93 894 221 570 349 478 477 138 605 355 733 94 861 58 989 46 94 896 222 572 350 480 478 140 606 357 734 96 862 60 990 6 95 898 223 574 351 482 479 142 607 359 735 98 863 62 991 2 96 900 224 576 352 484 480 144 608 361 736 100 864 64 992 4 97 967 225 975 353 983 481 991 609 999 737 1007 865 1015 993 1023 98 904 226 912 354 920 482 928 610 936 738 944 866 952 994 960 99 843 227 851 355 859 483 867 611 875 739 883 867 891 995 899 100 626 228 631 356 637 484 645 612 651 740 659 868 667 996 675 101 785 229 792 357 800 485 808 613 816 741 824 869 832 997 840 102 628 230 580 358 586 486 594 614 600 742 608 870 616 998 624 103 630 231 531 359 537 487 545 615 551 743 559 871 567 999 575 104 632 232 257 360 258 488 264 616 266 744 272 872 280 1000 288 105 730 233 736 361 743 489 751 617 759 745 767 873 775 1001 783 106 634 234 485 362 490 490 498 618 504 746 512 874 520 1002 528 107 636 235 442 363 445 491 453 619 459 747 467 875 475 1003 483 108 638 236 259 364 197 492 202 620 204 748 210 876 216 1004 224 109 640 237 362 365 364 493 371 621 375 749 383 877 391 1005 399 110 642 238 261 366 199 494 173 622 175 750 181 878 187 1006 195 111 644 239 263 367 201 495 123 623 146 751 129 879 135 1007 143 112 646 240 265 368 203 496 26 624 148 752 27 880 29 1008 35 113 677 241 683 369 689 497 697 625 704 753 712 881 720 1009 728 114 648 242 401 370 403 498 411 626 416 754 424 882 432 1010 440 115 650 243 325 371 327 499 333 627 336 755 344 883 352 1011 360 116 652 244 267 372 205 500 147 628 149 756 154 884 160 1012 168 117 654 245 290 373 292 501 298 629 300 757 307 885 315 1013 323 118 656 246 269 374 207 502 101 630 151 758 106 886 112 1014 120 119 658 247 271 375 209 503 82 631 153 759 85 887 91 1015 99 120 660 248 273 376 211 504 28 632 155 760 17 888 18 1016 24 121 662 249 275 377 226 505 232 633 234 761 240 889 247 1017 255 122 664 250 277 378 213 506 65 634 157 762 67 890 72 1018 80 123 666 251 279 379 215 507 50 635 159 763 52 891 55 1019 63 124 668 252 281 380 217 508 30 636 161 764 19 892 10 1020 15 125 670 253 283 381 219 509 37 637 163 765 39 893 41 1021 48 126 672 254 285 382 221 510 32 638 165 766 21 894 12 1022 8 127 674 255 287 383 223 511 34 639 167 767 23 895 14 1023 3 128 676 256 289 384 225 512 36 640 169 768 25 896 16 1024 1

Stored sequences have a nested feature. This helps reduce a quantity of required storage units. For example, based on the nested feature, a sequence with a length of M can be used to construct any sequence with a code length less than the length of M. Optionally, a sequence with a length of an odd power of 2 may be read from a longer sequence with a length of an even power of 2 based on the nested feature. For example, during construction of a sequence with a length of 8 (2³), sequence numbers less than or equal to 8 are selected in order from a sequence with a length of M=16 (2⁴) or a longer sequence with a length of an even power of 2 (for example, M=64, 256, 1024, or 4096), to form the sequence with the length of 8. For example, if the sequence numbers less than or equal to 8 are selected in order from the foregoing sequence with the length of M=4096, a sequence [5 7 6 2 4 8 3 1] can be obtained. According to this method, a sequence with a length of 2048 may be read from a mother code sequence with a length of 4096, and a sequence with a length of 512 may be read from a sequence with a length of 1024. In this embodiment, that the sequence with the length of 2048 is read from the foregoing sequence with the length of 4096 is used as an example for description. Sequence numbers of the sequence with the length of 2048 are shown in Table 3.

TABLE 3 Sequence with the length of 2048 Se- Se- Se- Se- Se- Se- Sequence Sequence quence quence quence quence quence quence Index number Index number Index number Index number Index number Index number Index number Index number 1 2026 257 1313 513 1014 769 1260 1025 847 1281 165 1537 459 1793 245 2 2028 258 1315 514 1016 770 1262 1026 849 1282 167 1538 1421 1794 66 3 2030 259 1317 515 1018 771 1264 1027 851 1283 169 1539 653 1795 1285 4 2032 260 1319 516 1020 772 1266 1028 853 1284 1816 1540 553 1796 1925 5 2034 261 1860 517 1022 773 1392 1029 855 1285 1648 1541 461 1797 1078 6 2036 262 1321 518 1024 774 1268 1030 1253 1286 1488 1542 462 1798 950 7 2038 263 1323 519 1784 775 1270 1031 1891 1287 698 1543 464 1799 389 8 2040 264 1325 520 1618 776 1272 1032 1046 1288 1567 1544 466 1800 1753 9 2042 265 1690 521 1458 777 1274 1033 918 1289 1338 1545 468 1801 889 10 2044 266 1327 522 680 778 1276 1034 857 1290 1194 1546 470 1802 773 11 2046 267 1329 523 1537 779 1278 1035 1719 1291 502 1547 472 1803 278 12 2048 268 1331 524 1308 780 1280 1036 858 1292 1992 1548 474 1804 614 13 2027 269 1333 525 1166 781 1282 1037 860 1293 1125 1549 476 1805 214 14 1765 270 1335 526 486 782 1284 1038 862 1294 993 1550 478 1806 158 15 1767 271 1337 527 1958 783 1286 1039 864 1295 416 1551 480 1807 68 16 1769 272 1339 528 1097 784 1288 1040 866 1296 810 1552 482 1808 1433 17 1771 273 1372 529 967 785 1290 1041 868 1297 301 1553 484 1809 665 18 1773 274 1341 530 401 786 1292 1042 870 1298 233 1554 1828 1810 565 19 1775 275 1343 531 789 787 1294 1043 1400 1299 51 1555 1660 1811 185 20 1777 276 1345 532 403 788 1296 1044 872 1300 1265 1556 1500 1812 473 21 1779 277 1347 533 405 789 1851 1045 874 1301 1903 1557 708 1813 133 22 1937 278 1349 534 407 790 1853 1046 876 1302 1058 1558 1579 1814 110 23 1781 279 1351 535 1236 791 1855 1047 878 1303 930 1559 1348 1815 70 24 1783 280 1353 536 1870 792 1857 1048 880 1304 375 1560 1204 1816 350 25 1785 281 1355 537 1031 793 1859 1049 882 1305 1731 1561 508 1817 89 26 1787 282 1357 538 905 794 1861 1050 884 1306 869 1562 2004 1818 71 27 1789 283 1359 539 409 795 1863 1051 886 1307 753 1563 1135 1819 73 28 1791 284 1361 540 1700 796 1865 1052 888 1308 266 1564 1003 1820 75 29 1793 285 1363 541 846 797 1970 1053 890 1309 596 1565 420 1821 77 30 1795 286 1365 542 734 798 1867 1054 892 1310 202 1566 820 1822 79 31 1850 287 1367 543 411 799 1869 1055 894 1311 148 1567 305 1823 81 32 1797 288 1369 544 579 800 1871 1056 896 1312 26 1568 237 1824 1840 33 1799 289 2039 545 413 801 1873 1057 898 1313 1412 1569 123 1825 1672 34 1801 290 1776 546 415 802 1875 1058 900 1314 646 1570 1275 1826 1512 35 1803 291 1610 547 417 803 1877 1059 1806 1315 548 1571 1915 1827 720 36 1805 292 1450 548 1382 804 1879 1060 1638 1316 174 1572 1068 1828 1591 37 1807 293 1158 549 628 805 1881 1061 1478 1317 458 1573 940 1829 1360 38 1809 294 1529 550 532 806 1882 1062 731 1318 124 1574 379 1830 1216 39 1811 295 1300 551 419 807 1884 1063 1557 1319 103 1575 1743 1831 520 40 1813 296 1159 552 442 808 1886 1064 1328 1320 28 1576 879 1832 2016 41 1815 297 1161 553 421 809 1888 1065 1184 1321 337 1577 763 1833 1147 42 1817 298 1949 554 423 810 1890 1066 733 1322 84 1578 270 1834 1015 43 1819 299 1163 555 425 811 1892 1067 1982 1323 67 1579 604 1835 432 44 1821 300 1165 556 427 812 1894 1068 1115 1324 30 1580 206 1836 832 45 1823 301 1167 557 429 813 1896 1069 983 1325 37 1581 150 1837 315 46 1825 302 1169 558 431 814 1898 1070 735 1326 32 1582 125 1838 247 47 1827 303 1171 559 433 815 1900 1071 800 1327 34 1583 1423 1839 55 48 1829 304 1173 560 435 816 1902 1072 737 1328 36 1584 655 1840 1287 49 1831 305 1175 561 437 817 1904 1073 739 1329 1818 1585 555 1841 1927 50 1833 306 1228 562 439 818 1906 1074 741 1330 1650 1586 177 1842 1080 51 1835 307 1862 563 441 819 1908 1075 1255 1331 1490 1587 463 1843 952 52 1837 308 1177 564 1786 820 1910 1076 1893 1332 1371 1588 126 1844 391 53 1839 309 1179 565 1620 821 1912 1077 1048 1333 1569 1589 128 1845 1755 54 1841 310 1181 566 1460 822 1914 1078 920 1334 1373 1590 130 1846 891 55 1843 311 1692 567 786 823 1916 1079 743 1335 1375 1591 341 1847 775 56 1845 312 1183 568 1539 824 1918 1080 1721 1336 1377 1592 132 1848 280 57 1847 313 1185 569 1310 825 1920 1081 859 1337 1994 1593 134 1849 616 58 1849 314 1187 570 1168 826 1922 1082 744 1338 1379 1594 136 1850 216 59 2029 315 1189 571 788 827 1924 1083 746 1339 1381 1595 138 1851 160 60 1766 316 1191 572 1960 828 1926 1084 748 1340 1383 1596 140 1852 29 61 1601 317 1193 573 1099 829 1928 1085 750 1341 1385 1597 142 1853 1435 62 1603 318 1195 574 969 830 1930 1086 752 1342 1387 1598 144 1854 667 63 1605 319 1374 575 790 831 1932 1087 754 1343 1389 1599 1830 1855 567 64 1607 320 1197 576 791 832 1934 1088 1402 1344 1391 1600 1662 1856 187 65 1609 321 1199 577 793 833 1936 1089 756 1345 1393 1601 1502 1857 475 66 1611 322 1201 578 795 834 1796 1090 758 1346 1905 1602 710 1858 135 67 1613 323 1203 579 797 835 1630 1091 760 1347 1395 1603 1581 1859 112 68 1939 324 1205 580 1238 836 1470 1092 762 1348 1397 1604 1350 1860 18 69 1615 325 1207 581 1872 837 1026 1093 764 1349 1399 1605 1206 1861 352 70 1617 326 1209 582 1033 838 1549 1094 766 1350 1733 1606 510 1862 91 71 1619 327 1211 583 907 839 1320 1095 768 1351 1401 1607 2006 1863 72 72 1621 328 1213 584 799 840 1176 1096 770 1352 1403 1608 1137 1864 10 73 1623 329 1215 585 1702 841 1028 1097 772 1353 1405 1609 1005 1865 41 74 1625 330 1217 586 848 842 1972 1098 774 1354 1407 1610 422 1866 12 75 1627 331 1219 587 801 843 1107 1099 776 1355 1409 1611 822 1867 14 76 1629 332 1221 588 803 844 1030 1100 778 1356 1411 1612 307 1868 16 77 1852 333 1223 589 805 845 1032 1101 780 1357 1413 1613 239 1869 1842 78 1631 334 1225 590 807 846 1034 1102 782 1358 1414 1614 102 1870 1674 79 1633 335 2041 591 809 847 1036 1103 784 1359 1416 1615 1277 1871 1514 80 1635 336 1778 592 811 848 1038 1104 1808 1360 1418 1616 1917 1872 722 81 1682 337 1612 593 1384 849 1040 1105 1640 1361 1420 1617 1070 1873 1593 82 1637 338 1452 594 813 850 1247 1106 1480 1362 1422 1618 942 1874 1362 83 1639 339 678 595 815 851 1883 1107 690 1363 1424 1619 381 1875 1218 84 1641 340 1531 596 817 852 1041 1108 1559 1364 1426 1620 1745 1876 522 85 1643 341 1302 597 819 853 1043 1109 1330 1365 1428 1621 881 1877 2018 86 1645 342 1160 598 821 854 1045 1110 1186 1366 1430 1622 765 1878 1149 87 1647 343 485 599 823 855 1712 1111 496 1367 1432 1623 272 1879 1017 88 1649 344 1951 600 825 856 1047 1112 1984 1368 1434 1624 606 1880 434 89 1651 345 1092 601 827 857 1049 1113 1117 1369 1436 1625 208 1881 834 90 1653 346 964 602 829 858 1051 1114 985 1370 1438 1626 152 1882 317 91 1655 347 487 603 831 859 1053 1115 410 1371 1440 1627 104 1883 249 92 1657 348 787 604 833 860 1055 1116 802 1372 1442 1628 1425 1884 57 93 1659 349 489 605 835 861 1057 1117 295 1373 1444 1629 657 1885 1289 94 1661 350 491 606 837 862 1059 1118 258 1374 1820 1630 557 1886 1929 95 1663 351 493 607 839 863 1394 1119 260 1375 1652 1631 179 1887 1082 96 1665 352 1230 608 841 864 1061 1120 1257 1376 1492 1632 465 1888 954 97 1667 353 1864 609 1788 865 1063 1121 1895 1377 700 1633 127 1889 393 98 1669 354 1027 610 1622 866 1065 1122 1050 1378 1571 1634 105 1890 1757 99 1671 355 903 611 1462 867 1067 1123 922 1379 1340 1635 107 1891 893 100 1673 356 495 612 682 868 1069 1124 369 1380 1196 1636 343 1892 777 101 1675 357 1694 613 1541 869 1071 1125 1723 1381 627 1637 109 1893 282 102 1677 358 844 614 1312 870 1073 1126 861 1382 1996 1638 111 1894 618 103 1679 359 732 615 1170 871 1075 1127 745 1383 1127 1639 113 1895 218 104 1681 360 497 616 488 872 1077 1128 261 1384 995 1640 115 1896 162 105 2031 361 577 617 1962 873 1079 1129 589 1385 629 1641 117 1897 38 106 1768 362 499 618 1101 874 1081 1130 263 1386 812 1642 119 1898 1437 107 1602 363 501 619 971 875 1083 1131 265 1387 631 1643 121 1899 669 108 1445 364 503 620 402 876 1085 1132 267 1388 633 1644 1832 1900 569 109 1447 365 1376 621 792 877 1087 1133 1404 1389 635 1645 1664 1901 189 110 1522 366 626 622 290 878 1089 1134 638 1390 1267 1646 1504 1902 477 111 1449 367 530 623 292 879 1798 1135 542 1391 1907 1647 712 1903 137 112 1451 368 505 624 294 880 1632 1136 269 1392 1060 1648 1583 1904 114 113 1453 369 507 625 1240 881 1472 1137 452 1393 932 1649 1352 1905 40 114 1941 370 509 626 1874 882 902 1138 271 1394 637 1650 1208 1906 354 115 1455 371 511 627 1035 883 1551 1139 273 1395 1735 1651 512 1907 93 116 1457 372 513 628 909 884 1322 1140 275 1396 871 1652 2008 1908 74 117 1459 373 515 629 362 885 1178 1141 331 1397 755 1653 1139 1909 42 118 1461 374 517 630 1704 886 904 1142 277 1398 639 1654 1007 1910 43 119 1463 375 519 631 850 887 1974 1143 279 1399 641 1655 424 1911 45 120 1465 376 521 632 736 888 1109 1144 281 1400 643 1656 824 1912 47 121 1467 377 523 633 296 889 977 1145 283 1401 645 1657 309 1913 49 122 1469 378 525 634 581 890 906 1146 285 1402 647 1658 241 1914 1844 123 1854 379 527 635 298 891 908 1147 287 1403 1415 1659 53 1915 1676 124 1471 380 529 636 300 892 910 1148 289 1404 648 1660 1279 1916 1516 125 1473 381 2043 637 302 893 912 1149 1810 1405 650 1661 1919 1917 724 126 1475 382 1938 638 1386 894 914 1150 1642 1406 652 1662 1072 1918 1595 127 1684 383 1940 639 630 895 1249 1151 1482 1407 654 1663 944 1919 1364 128 1477 384 1942 640 534 896 1885 1152 692 1408 656 1664 383 1920 1220 129 1479 385 1944 641 304 897 1042 1153 1561 1409 658 1665 1747 1921 524 130 1481 386 1946 642 444 898 915 1154 1332 1410 660 1666 883 1922 2020 131 1483 387 1948 643 306 899 917 1155 1188 1411 662 1667 767 1923 1151 132 1485 388 1950 644 308 900 1714 1156 578 1412 664 1668 274 1924 1019 133 1487 389 1952 645 310 901 919 1157 1986 1413 666 1669 608 1925 436 134 1489 390 1953 646 325 902 921 1158 1119 1414 668 1670 210 1926 836 135 1491 391 1955 647 312 903 923 1159 987 1415 670 1671 154 1927 319 136 1493 392 1957 648 314 904 925 1160 580 1416 672 1672 27 1928 251 137 1495 393 1959 649 316 905 927 1161 804 1417 674 1673 1427 1929 59 138 1497 394 1961 650 318 906 929 1162 582 1418 676 1674 659 1930 1291 139 1499 395 1963 651 320 907 931 1163 584 1419 1822 1675 559 1931 1931 140 1501 396 1965 652 322 908 1396 1164 586 1420 1654 1676 181 1932 1084 141 1503 397 1967 653 324 909 933 1165 1259 1421 1494 1677 467 1933 956 142 1505 398 1969 654 1790 910 935 1166 1897 1422 702 1678 129 1934 395 143 1507 399 1971 655 1624 911 937 1167 1052 1423 1573 1679 106 1935 1759 144 1509 400 1973 656 1464 912 939 1168 924 1424 1342 1680 17 1936 895 145 1511 401 1975 657 684 913 941 1169 588 1425 1198 1681 345 1937 779 146 1513 402 1977 658 1543 914 943 1170 1725 1426 531 1682 86 1938 284 147 1515 403 1979 659 1314 915 945 1171 863 1427 1998 1683 69 1939 620 148 1517 404 1981 660 1172 916 947 1172 747 1428 1129 1684 19 1940 220 149 1519 405 1983 661 490 917 949 1173 590 1429 997 1685 39 1941 164 150 1521 406 1985 662 1964 918 951 1174 591 1430 533 1686 21 1942 31 151 2033 407 1987 663 1103 919 953 1175 593 1431 814 1687 23 1943 1439 152 1770 408 1989 664 973 920 955 1176 595 1432 535 1688 25 1944 671 153 1604 409 1991 665 404 921 957 1177 597 1433 537 1689 1834 1945 571 154 1446 410 1993 666 794 922 959 1178 1406 1434 539 1690 1666 1946 191 155 677 411 1995 667 291 923 961 1179 640 1435 1269 1691 1506 1947 479 156 1524 412 1997 668 226 924 1800 1180 599 1436 1909 1692 714 1948 139 157 1297 413 1999 669 228 925 1634 1181 601 1437 1062 1693 1585 1949 116 158 1157 414 2001 670 1242 926 1474 1182 603 1438 934 1694 1354 1950 20 159 679 415 2003 671 1876 927 688 1183 605 1439 541 1695 1210 1951 356 160 1943 416 2005 672 1037 928 1553 1184 607 1440 1737 1696 514 1952 95 161 1090 417 2007 673 911 929 1324 1185 609 1441 873 1697 2010 1953 76 162 962 418 2009 674 364 930 1180 1186 611 1442 757 1698 1141 1954 11 163 681 419 2011 675 1706 931 494 1187 613 1443 543 1699 1009 1955 44 164 785 420 2013 676 852 932 1976 1188 615 1444 598 1700 426 1956 5 165 683 421 2015 677 738 933 1111 1189 617 1445 545 1701 826 1957 7 166 685 422 2017 678 257 934 979 1190 619 1446 547 1702 326 1958 9 167 687 423 2019 679 583 935 408 1191 621 1447 549 1703 328 1959 1846 168 1226 424 2021 680 230 936 798 1192 623 1448 1417 1704 330 1960 1678 169 1856 425 2023 681 232 937 363 1193 625 1449 649 1705 1281 1961 1518 170 1025 426 2025 682 234 938 365 1194 1812 1450 550 1706 1921 1962 726 171 901 427 2045 683 1388 939 367 1195 1644 1451 552 1707 1074 1963 1597 172 689 428 1780 684 632 940 1251 1196 1484 1452 554 1708 946 1964 1366 173 1686 429 1614 685 536 941 1887 1197 694 1453 556 1709 385 1965 1222 174 842 430 1454 686 236 942 1044 1198 1563 1454 558 1710 1749 1966 526 175 730 431 1091 687 446 943 916 1199 1334 1455 560 1711 885 1967 2022 176 691 432 1533 688 238 944 368 1200 1190 1456 562 1712 769 1968 1153 177 693 433 1304 689 240 945 1716 1201 498 1457 564 1713 332 1969 1021 178 695 434 1162 690 242 946 856 1202 1988 1458 566 1714 610 1970 438 179 697 435 1093 691 327 947 742 1203 1121 1459 568 1715 334 1971 838 180 699 436 1954 692 244 948 370 1204 989 1460 570 1716 336 1972 321 181 1370 437 1094 693 246 949 587 1205 412 1461 572 1717 338 1973 253 182 701 438 1096 694 248 950 372 1206 806 1462 574 1718 1429 1974 61 183 703 439 1098 695 250 951 374 1207 297 1463 576 1719 661 1975 1293 184 705 440 1100 696 252 952 376 1208 229 1464 1824 1720 561 1976 1933 185 707 441 1102 697 254 953 1398 1209 198 1465 1656 1721 340 1977 1086 186 709 442 1104 698 256 954 636 1210 1261 1466 1496 1722 469 1978 958 187 711 443 1106 699 1792 955 540 1211 1899 1467 704 1723 342 1979 397 188 713 444 1232 700 1626 956 378 1212 1054 1468 1575 1724 344 1980 1761 189 715 445 1866 701 1466 957 450 1213 926 1469 1344 1725 346 1981 897 190 717 446 1108 702 686 958 380 1214 371 1470 1200 1726 347 1982 781 191 719 447 1110 703 1545 959 382 1215 1727 1471 504 1727 349 1983 286 192 721 448 1112 704 1316 960 384 1216 865 1472 2000 1728 351 1984 622 193 723 449 1696 705 1174 961 386 1217 749 1473 1131 1729 353 1985 222 194 725 450 1114 706 492 962 388 1218 262 1474 999 1730 355 1986 166 195 727 451 1116 707 1966 963 390 1219 592 1475 418 1731 357 1987 33 196 729 452 1118 708 1105 964 392 1220 199 1476 816 1732 359 1988 1441 197 2035 453 1120 709 975 965 394 1221 201 1477 303 1733 361 1989 673 198 1772 454 1122 710 406 966 396 1222 203 1478 235 1734 1836 1990 573 199 1606 455 1124 711 796 967 398 1223 1408 1479 171 1735 1668 1991 193 200 1523 456 1126 712 293 968 400 1224 642 1480 1271 1736 1508 1992 481 201 1525 457 1378 713 227 969 1802 1225 544 1481 1911 1737 716 1993 141 202 1526 458 1128 714 50 970 1683 1226 205 1482 1064 1738 1587 1994 118 203 1528 459 1130 715 1244 971 1685 1227 454 1483 936 1739 1356 1995 22 204 1530 460 1132 716 1878 972 1687 1228 207 1484 377 1740 1212 1996 358 205 1532 461 1134 717 1039 973 1689 1229 209 1485 1739 1741 516 1997 97 206 1945 462 1136 718 913 974 1691 1230 211 1486 875 1742 2012 1998 78 207 1534 463 1138 719 366 975 1693 1231 333 1487 759 1743 1143 1999 13 208 1536 464 1140 720 1708 976 1695 1232 213 1488 268 1744 1011 2000 46 209 1538 465 1142 721 854 977 1978 1233 215 1489 600 1745 428 2001 6 210 1540 466 1144 722 740 978 1697 1234 217 1490 204 1746 828 2002 2 211 1542 467 1146 723 259 979 1699 1235 219 1491 173 1747 311 2003 4 212 1544 468 1148 724 585 980 1701 1236 221 1492 175 1748 243 2004 1848 213 1546 469 1150 725 197 981 1703 1237 223 1493 1419 1749 83 2005 1680 214 1548 470 1152 726 145 982 1705 1238 225 1494 651 1750 1283 2006 1520 215 1858 471 1154 727 52 983 1707 1239 1814 1495 551 1751 1923 2007 728 216 1550 472 1156 728 1390 984 1709 1240 1646 1496 176 1752 1076 2008 1599 217 1552 473 2047 729 634 985 1711 1241 1486 1497 460 1753 948 2009 1368 218 1554 474 1782 730 538 986 1889 1242 696 1498 178 1754 387 2010 1224 219 1688 475 1616 731 170 987 1713 1243 1565 1499 180 1755 1751 2011 528 220 1556 476 1456 732 448 988 1715 1244 1336 1500 182 1756 887 2012 2024 221 1558 477 963 733 122 989 1717 1245 1192 1501 339 1757 771 2013 1155 222 1560 478 1535 734 101 990 1718 1246 500 1502 184 1758 276 2014 1023 223 1562 479 1306 735 54 991 1720 1247 1990 1503 186 1759 612 2015 440 224 1564 480 1164 736 329 992 1722 1248 1123 1504 188 1760 212 2016 840 225 1566 481 965 737 82 993 1724 1249 991 1505 190 1761 156 2017 323 226 1568 482 1956 738 65 994 1726 1250 414 1506 192 1762 85 2018 255 227 1570 483 1095 739 56 995 1728 1251 808 1507 194 1763 1431 2019 63 228 1572 484 966 740 58 996 1730 1252 299 1508 196 1764 663 2020 1295 229 1574 485 968 741 60 997 1732 1253 231 1509 1826 1765 563 2021 1935 230 1576 486 970 742 62 998 1734 1254 146 1510 1658 1766 183 2022 1088 231 1578 487 972 743 64 999 1736 1255 1263 1511 1498 1767 471 2023 960 232 1580 488 974 744 1794 1000 1738 1256 1901 1512 706 1768 131 2024 399 233 1582 489 976 745 1628 1001 1740 1257 1056 1513 1577 1769 108 2025 1763 234 1584 490 1234 746 1468 1002 1742 1258 928 1514 1346 1770 87 2026 899 235 1586 491 1868 747 1227 1003 1744 1259 373 1515 1202 1771 348 2027 783 236 1588 492 1029 748 1547 1004 1746 1260 1729 1516 506 1772 88 2028 288 237 1590 493 978 749 1318 1005 1748 1261 867 1517 2002 1773 90 2029 624 238 1592 494 980 750 1229 1006 1750 1262 751 1518 1133 1774 92 2030 224 239 1594 495 1698 751 1231 1007 1752 1263 264 1519 1001 1775 94 2031 168 240 1596 496 982 752 1968 1008 1754 1264 594 1520 443 1776 96 2032 35 241 1598 497 984 753 1233 1009 1756 1265 200 1521 818 1777 98 2033 1443 242 1600 498 986 754 1235 1010 1758 1266 147 1522 445 1778 100 2034 675 243 2037 499 988 755 1237 1011 1760 1267 149 1523 447 1779 1838 2035 575 244 1774 500 990 756 1239 1012 1762 1268 1410 1524 449 1780 1670 2036 195 245 1608 501 992 757 1241 1013 1764 1269 644 1525 1273 1781 1510 2037 483 246 1448 502 994 758 1243 1014 1804 1270 546 1526 1913 1782 718 2038 143 247 1298 503 1380 759 1245 1015 1636 1271 172 1527 1066 1783 1589 2039 120 248 1527 504 996 760 1246 1016 1476 1272 456 1528 938 1784 1358 2040 24 249 1299 505 998 761 1880 1017 843 1273 151 1529 451 1785 1214 2041 360 250 1301 506 1000 762 1248 1018 1555 1274 153 1530 1741 1786 518 2042 99 251 1303 507 1002 763 1250 1019 1326 1275 155 1531 877 1787 2014 2043 80 252 1947 508 1004 764 1252 1020 1182 1276 335 1532 761 1788 1145 2044 15 253 1305 509 1006 765 1710 1021 845 1277 157 1533 453 1789 1013 2045 48 254 1307 510 1008 766 1254 1022 1980 1278 159 1534 602 1790 430 2046 8 255 1309 511 1010 767 1256 1023 1113 1279 161 1535 455 1791 830 2047 3 256 1311 512 1012 768 1258 1024 981 1280 163 1536 457 1792 313 2048 1

In the embodiments, the device may be divided into functional modules based on the foregoing method examples. For example, each functional module may be obtained through division based on each corresponding function, or two or more functions may be integrated into one module. The integrated module may be implemented in a form of hardware, or may be implemented in a form of a software functional module. It should be noted that, in the embodiments, division into the modules is an example and merely logical function division, and may be other division in an actual implementation.

FIG. 6 is a schematic structural diagram of a communications device according to an embodiment. The communications device shown in FIG. 6 may be configured to perform some or all functions of the communications device in the method embodiment described in FIG. 3. The communications device shown in FIG. 6 may include a processing module 601 and a communications module 602.

The communications module 602 is configured to obtain a to-be-encoded information bit sequence. The processing module 601 is configured to encode the to-be-encoded information bit sequence based on a binary vector P₁ of a first code, to obtain an encoded bit sequence, where P₁ is determined based on a binary vector P₂ of a second code and a binary vector P₃ of a third code, P₁ indicates an information bit and a frozen bit of the first code, P₂ indicates an information bit and a frozen bit of the second code, P₃ indicates an information bit and a frozen bit of the third code, a code length of the first code is n₃, a quantity of information bits of the first code is k₁, a code length of the second code is n₂, a quantity of information bits of the second code is k₂, a code length of the third code is n₃, a quantity of information bits of the third code is k₃, n₁=n₂*n₃, and k₁=k₂*k₃. The processing module 601 is further configured to output the encoded bit sequence.

Optionally, P₁=P₂⊗P₃.

Optionally, n₂=n₃ and k₂=k₃.

Optionally, P₂ is equal to P₃.

Optionally, k₁=k₄, and k₄ is a length of the to-be-encoded information bit sequence.

Optionally, k₄<k₁, k₁=┌√{square root over (k₄)}┐², and k₄ is a length of the to-be-encoded information bit sequence.

Optionally, that the processing module 601 encodes the to-be-encoded information bit sequence based on a binary vector P₁ of a first code is implemented in the following manner: determining, based on P₁, a binary vector P₄ corresponding to a fourth code, where P₄ indicates an information bit and a frozen bit of the fourth code, a code length of the fourth code is n₄, a quantity of information bits of the fourth code is k₄, and n₄=n₁; and encoding the to-be-encoded information bit sequence based on P₄.

Optionally, a set S₂ is a subset of a set S₁, the set S₁ is an information bit set including the information bit indicated by P₁, and S₂ is an information bit set including the information bit indicated by P₄.

Optionally, that the processing module 601 determines, based on P₁, a binary vector P₄ corresponding to a fourth code is implemented in the following manner: determining a set S₃ from the set S₁, where when an information bit included in the set S₃ is changed to a frozen bit, at least one information bit of a first inner code can be changed to a frozen bit in a first encoding process; determining a first information bit from the set S₃; changing the first information bit in P₁ to a frozen bit, to obtain a binary vector P₅; and obtaining the binary vector P₄ corresponding to the fourth code based on the binary vector P₅.

Optionally, the set S₃ includes a plurality of information bits; and compared with another information bit in the set S₃, when the first information bit in the set S₃ is changed to a frozen bit, an information bit that is of the first inner code and that is changed to a frozen bit has a lowest reliability rank.

Optionally, that the processing module 601 obtains the binary vector P₄ corresponding to the fourth based on the binary vector P₅ is implemented in the following manner: determining a set S₄ from an information bit indicated by P₅, where when an information bit included in the set S₄ is changed to a frozen bit, at least one information bit of a second inner code can be changed to a frozen bit in a second encoding process, the first inner code is an outer code for the second encoding process, and the second inner code is an outer code for the first encoding process; determining a second information bit from the set S₄; changing the second information bit in P₅ to a frozen bit, to obtain a binary vector P₆; and obtaining the binary vector P₄ corresponding to the fourth code based on the binary vector P₆.

Optionally, the set S₄ includes a plurality of information bits; and compared with another information bit in the set S₄, when the second information bit in the set S₄ is changed to a frozen bit, an information bit that is of the second inner code and that is changed to a frozen bit has a lowest reliability rank.

Optionally, n₁, n₂, and n₃ each are an integral power of 2.

FIG. 6 is a schematic structural diagram of a communications device according to an embodiment. The communications device shown in FIG. 6 may be configured to perform some or all functions of the communications device in the method embodiments. The communications device shown in FIG. 6 may include a processing module 601 and a communications module 602.

The communications module 602 is configured to obtain a to-be-encoded information bit sequence. The processing module 601 is configured to encode the to-be-encoded information bit sequence based on a binary vector P₁ of a first code, to obtain an encoded bit sequence, where P₁ indicates an information bit and a frozen bit of the first code, P₁ is determined based on a target sequence and a quantity k₁ of information bits of the first code, the quantity k₁ of information bits of the first code is equal to a length of the to-be-encoded information bit sequence, a code length of the first code is m, the target sequence is a sequence that is extracted from a stored sequence with a length of M and that includes a sequence number less than or equal to m, the sequence with the length of M includes a sequence number corresponding to each of M bits, and M is greater than or equal to m. The processing module 601 is further configured to output the encoded bit sequence.

Optionally, the processing module 601 is further configured to determine a set S₁ from an information bit indicated by a binary vector P₂ of a second code, where when an information bit included in the set S₁ is changed to a frozen bit, at least one information bit of a first inner code can be changed to a frozen bit in a first encoding process. The processing module 601 is further configured to determine a first information bit from the set S₁. The processing module 601 is further configured to change the first information bit in P₂ to a frozen bit, to obtain a binary vector P₃ of a third code, where a code length of the second code is M, a quantity of information bits of the second code is K, a code length of the third code is M, and a quantity of information bits of the third code is K−1. The processing module 601 is further configured to: determine that a sequence number corresponding to the first information bits is K, and traverse K from M to 1, to determine a sequence number corresponding to each bit in the sequence with the length of M.

Optionally, the set S₁ includes a plurality of information bits; and compared with another information bit in the set S₁, when the first information bit in the set S₁ is changed to a frozen bit, an information bit that is of the first inner code and that is changed to a frozen bit has a lowest reliability rank.

FIG. 7 is a schematic structural diagram of a communications device disclosed in an embodiment. As shown in FIG. 7, the communications device includes a processor 701, a memory 702, and a communications interface 703. The processor 701, the memory 702, and the communications interface 703 are connected.

The processor 701 may be a central processing unit (CPU), a general-purpose processor, a coprocessor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or another programmable logic device, a transistor logic device, a hardware component, or any combination thereof. Alternatively, the processor 701 may be a combination of processors implementing a computing function, for example, a combination of one or more microprocessors, or a combination of a DSP and a microprocessor.

The communications interface 703 is configured to implement communication between the communications device and another communications device or communication between other communications component in the same communications device.

The processor 701 invokes program code stored in the memory 702, to perform the steps performed by the communications device in the foregoing method embodiments. The memory 702 is further configured to store data cached in a process of performing the foregoing methods. Optionally, the memory 702 is further configured to store the sequence in Table 1 or a similar sequence. The memory 702 and the processor 701 are coupled to each other. Optionally, the memory 702 and the processor 701 may be integrated.

An embodiment further provides a computer-readable storage medium. The computer-readable storage medium stores instructions. When the instructions are run on a processor, the method procedures in the foregoing method embodiments are implemented.

An embodiment further provides a computer program product. When the computer program product runs on a processor, the method procedures in the foregoing method embodiments are implemented.

An embodiment further provides a chip system. The chip system includes a processor, configured to support a communications device in implementing functions in the foregoing embodiments, for example, generating or processing data and/or information used in the foregoing methods.

In a possible implementation, the chip system may further include a memory. The memory is configured to store necessary program instructions and data. The chip system may include a chip, or may include a chip and another discrete component.

Based on a same inventive concept, a problem-resolving principle of the communications device provided in the embodiments is similar to a problem-resolving principle of the access network device or the first node in the method embodiments. Therefore, for implementations of each device, refer to the implementations of the method. For brevity, details are not described herein again.

In the foregoing embodiments, the descriptions of each embodiment have respective focuses. For a part that is not described in detail in an embodiment, refer to related descriptions in other embodiments.

Finally, it should be noted that the foregoing embodiments are merely intended for describing the solutions and are intended to be non-limiting. Although foregoing embodiments are described in detail, persons of ordinary skill in the art should understand that they may still make modifications to the solutions described in the foregoing embodiments or make equivalent replacements to some or all features thereof, without departing from the scope of the solutions of the embodiments. 

1. An encoding method, comprising: obtaining a to-be-encoded information bit sequence; encoding the to-be-encoded information bit sequence based on a binary vector P₁ of a first code, to obtain an encoded bit sequence, wherein P₁ is determined based on a binary vector P₂ of a second code and a binary vector P₃ of a third code, P₁ indicates an information bit and a frozen bit of the first code, P₂ indicates an information bit and a frozen bit of the second code, P₃ indicates an information bit and a frozen bit of the third code, a code length of the first code is n₁, a quantity of information bits of the first code is k₁, a code length of the second code is n₂, a quantity of information bits of the second code is k₂, a code length of the third code is n₃, a quantity of information bits of the third code is k₃, n₁=n₂*n₃, and k₁=k₂*k₃; and outputting the encoded bit sequence.
 2. The method according to claim 1, wherein P₁=P₂⊗P₃.
 3. The method according to claim 1, wherein n₂=n₃ and k₂=k₃.
 4. The method according to claim 3, wherein P₂ is equal to P₃.
 5. The method according to claim 1, wherein k₁=k₄, and k₄ is a length of the to-be-encoded information bit sequence.
 6. The method according to claim 1, wherein k₄<k₁, k₁=┌k₄┐², and k₄ is a length of the to-be-encoded information bit sequence.
 7. The method according to claim 6, wherein the encoding of the to-be-encoded information bit sequence based on a binary vector P₁ of a first code comprises: determining, based on P₁, a binary vector P₄ corresponding to a fourth code, wherein P₄ indicates an information bit and a frozen bit of the fourth code, a code length of the fourth code is n₄, a quantity of information bits of the fourth code is k₄, and n₄=n₁; and encoding the to-be-encoded information bit sequence based on P₄.
 8. The method according to claim 7, wherein a set S₂ is a subset of a set S₁, the set S₁ is an information bit set comprising the information bit indicated by P₁, and S₂ is an information bit set comprising the information bit indicated by P₄.
 9. The method according to claim 8, wherein the determining, based on P₁, of a binary vector P₄ corresponding to a fourth code comprises: determining a set S₃ from the set S₁, wherein when an information bit comprised in the set S₃ is changed to a frozen bit, at least one information bit of a first inner code can be changed to a frozen bit in a first encoding process; determining a first information bit from the set S₃; changing the first information bit in P₁ to a frozen bit, to obtain a binary vector P₅; and obtaining the binary vector P₄ corresponding to the fourth code based on the binary vector P₅.
 10. The method according to claim 9, wherein the set S₃ comprises a plurality of information bits; and compared with another information bit in the set S₃, when the first information bit in the set S₃ is changed to a frozen bit, an information bit that is of the first inner code and that is changed to a frozen bit has a lowest reliability rank.
 11. The method according to claim 9, wherein the obtaining the corresponding to the fourth code based on the binary vector P₅ comprises: determining a set S₄ from an information bit indicated by P₅, wherein when an information bit comprised in the set S₄ is changed to a frozen bit, at least one information bit of a second inner code can be changed to a frozen bit in a second encoding process, the first inner code is an outer code for the second encoding process, and the second inner code is an outer code for the first encoding process; determining a second information bit from the set S₄; changing the second information bit in P₅ to a frozen bit, to obtain a binary vector P₆; and obtaining the binary vector P₄ corresponding to the fourth code based on the binary vector P₆.
 12. The method according to claim 11, wherein the set S₄ comprises a plurality of information bits; and, compared with another information bit in the set S₄, when the second information bit in the set S₄ is changed to a frozen bit, an information bit that is of the second inner code and that is changed to a frozen bit has a lowest reliability rank.
 13. The method according to claim 1, wherein n₁, n₂, and n₃ each are an integral power of
 2. 14. The method according to claim 1, wherein the encoding the to-be-encoded information bit sequence based on a binary vector P₁ of a first code, to obtain an encoded bit sequence comprises: determining a binary vector P₇ of a seventh code based on the binary vector P₁ of the first code, wherein the binary vector P₇ indicates an information bit, a frozen bit, and a non-transmitted bit of the seventh code, a code length of the seventh code is n₇, a quantity of information bits of the seventh code is k₇, a quantity of non-transmitted bits of the seventh code is n₁−n₇, k₇ is equal to the length of the to-be-encoded information bit sequence, n₇ is an integer greater than k₇, ${n_{1} = 4^{\lceil\frac{\log_{2}{(n_{7})}}{2}\rceil}},$ and k₁ is greater than or equal to k₇; encoding the to-be-encoded information bit sequence based on the binary vector P₇ of the seventh code, to obtain an encoded first bit sequence with a length of n₁; and removing the non-transmitted bit from the first bit sequence, to obtain a second bit sequence with a length of n₇; and the outputting the encoded bit sequence comprises: outputting the second bit sequence.
 15. The method according to claim 14, wherein k₇=k₁+n₁−n₇, and the determining of a binary vector P₇ of a seventh code based on the binary vector P₁ of the first code comprises: sequentially changing, according to a first preset rule, elements indicating information bits in P₁ to elements indicating non-transmitted bits, until a quantity of the elements indicating the non-transmitted bits in P₁ is equal to n₁−n₇, to obtain the binary vector P₇, wherein a value of the non-transmitted bit is independent of a value of the information bit of the seventh code.
 16. An encoding method, comprising: obtaining a to-be-encoded information bit sequence; encoding the to-be-encoded information bit sequence based on a binary vector P₁ of a first code, to obtain an encoded bit sequence, wherein P₁ indicates an information bit and a frozen bit of the first code, P₁ is determined based on a target sequence and a quantity k₁ of information bits of the first code, the quantity k₁ of information bits of the first code is equal to a length of the to-be-encoded information bit sequence, a code length of the first code is n₁, the target sequence is a sequence that is extracted from a stored sequence with a length of M and that comprises a sequence number less than or equal to n₁, the sequence with the length of M comprises a sequence number corresponding to each of the M bits in the stored sequence, and M is greater than or equal to n₁; and outputting the encoded bit sequence.
 17. The method according to claim 16, further comprising: determining a set S₁ from an information bit indicated by a binary vector P₂ of a second code, wherein when an information bit comprised in the set S₁ is changed to a frozen bit, at least one information bit of a first inner code can be changed to a frozen bit in a first encoding process; and determining a first information bit from the set S₁; changing the first information bit in P₂ to a frozen bit, to obtain a binary vector P₃ of a third code, wherein a code length of the second code is M, a quantity of information bits of the second code is K, a code length of the third code is M, and a quantity of information bits of the third code is K−1; determining that a sequence number corresponding to the first information bit is K; and traversing K from M to 1, to determine a sequence number corresponding to each bit in the sequence with the length of M.
 18. The method according to claim 17, wherein the set S₁ comprises a plurality of information bits; and compared with another information bit in the set S₁, when the first information bit in the set S₁ is changed to a frozen bit, an information bit that is of the first inner code and that is changed to a frozen bit has a lowest reliability rank.
 19. A communications device, comprising: at least one non-transitory memory, wherein the at least one non-transitory memory comprises computer-readable instructions; and at least one processor, wherein when executing the computer-readable instructions, the at least one processor is enabled to: obtain a to-be-encoded information bit sequence; and encode the to-be-encoded information bit sequence based on a binary vector P₁ of a first code, to obtain an encoded bit sequence, wherein P₁ is determined based on a binary vector P₂ of a second code and a binary vector P₃ of a third code, P₁ indicates an information bit and a frozen bit of the first code, P₂ indicates an information bit and a frozen bit of the second code, P₃ indicates an information bit and a frozen bit of the third code, a code length of the first code is n₁, a quantity of information bits of the first code is k₁, a code length of the second code is n₂, a quantity of information bits of the second code is k₂, a code length of the third code is n₃, a quantity of information bits of the third code is k₃, n₁=n₂*n₃, and k₁=k₂*k₃; and to output the encoded bit sequence.
 20. The communications device according to claim 19, wherein P₁=P₂ ⊗P₃. 